^^ ELECTRIC INTERLOCKING I I I I ■ J ■i i ■i 1 1 C^ENERAL RAILWAY gie^Al (]OMPANY { THE UNIVERSITY OF ILLINOIS LIBRARY <55fo G^Se USviAiiY JIKIVWSITyOFILLIHOISLIBBWY . MAR 1 mi) twYEfisin flf luion ELECTRIC INTERLOCKING HANDBOOK BY THE . ENGINEERING STAFF OF THE GENERAL RAILWAY SIGNAL COMPANY WITH AN INTRODUCTION BY WILMER W. SALMON Henry M. Sperry, Editor M. Am, Soc. C. E. Paul E. Carter, Assistant Editor Sherman A. Benedict, Illustrator Price 31.00 Second Reprixt of First Edition GENERAL RAILWAY S IGNAL C OMPANY Rochester, N. Y.. 1917 COPYRIGHT, 1913, BY JENERAL. RAILWAY SIGNAL CO. ROCHESTER, N. Y. The Du Bcis Press of Rochester (ebb 9 i The Engineering Staff OF THE General Railway Signal Company WiNTHKOP K. Howe, Chief Engineer M. A. I. E. E. Frank L. Dodgson, Consulting Engineer Salisbury M, Day, Principal Assistant Engineer Sedwick N. Wight, Commercial Engineer \inslie T. Carter, Electrical Engineer 441318 GENERAL RAILWAY SIGNAL COMPANY - WILMER W. SALMON PRESIDENT AND GENERAL AL\NAGER GEORGE D. MORGAN CLARENCE H. LITTELL VICE-PRESIDENT SECRETARY Principal Office and Works Rochester, N. Y. BRANCH OFFICES: New York Office Hudson Terminal Building, 30 Church Street New York, N. Y. Chicago Office People's Gas Building, 12? Sopjrn Michigan Aventje Chicago, III. CANADIAN AGENCY General. Railway Signal Company of Canada, Ltd. Lachine, p. Q. AUSTRALASIAN AGENCIES R. W. Cameron & Co. Sydney 16 Spring Street Melbourne 34 Queen Street Brisbane New ZeaLu\nd Chambers Perth Selborne Chambers Wellington, N. Z. ... Australasia Chambers GENERAL RAILWAY SIGNAL COMPANY Engineers, ^VL^nufacturers, and Erectors of Railway Signal Appll\nces PRODUCTS Electric Interlocking mechan^cal interlocking Automatic Block Signals, Direct Curren-t Automatic Block Signals, Alternating Current IManuallt Operated Block Signals Telephone Selectors Mil ^ t ^"^ INTRODUCTION INTERLOCKING is of English origin, numerous patents having been granted in England for manually operated interlocking devices from 1856 to 1867, at which later date was first disclosed by Saxby a satisfactory means for obtaining what is now known as "preliminary latch locking." The rapidity with which this valuable system was adopted in England is indicated by the fact that six years later, in 1873, 13,000 mechanical interlocking levers were employed on the London & Northwestern Railway alone, at which time not a single lever was in use in the United States, the first experi- mental installation having been made in this country by Messrs. Toucey and Buchanan at Spuyten Duyvil Junction, New York City, in 1874, and the first important installations on a commercial basis having been made by the Manhattan Elevated Lines of New York City with machines of the Saxby-Farmer type, built by the Jackson Manufacturing Co. of Harrisburg, Pa., in 1877-78. Very soon after American railways had gained a little experi- ence with mechanical interlocking plants, it was felt that there were many situations where great economies could be effected and more satisfactory operation obtained if switches and signals could be successfully worked by power instead of manually. For precisely the same reason — viz : saving of labor — that English raihvays were first led to concentrate in a single frame the theretofore widely separated levers for the operation of switches and signals — thus leading up to the idea of interlocking — so the much higher cost of labor in the United States than in England caused the American railways to demand an interlocking that would afford means for operat- ing switches and signals over greater distances and with fewer operators than were required under the English method. The first concrete response of the American inventor to this demand was the Hydro-Pneumatic Interlocking installed in 1884 near Bound Brook, N. J., at the crossing of the P. & R. and L. V. R. R. From 1884 to 1891, eighteen Hydro- Pneumatic plants, having 482 levers, were installed _on six 6 GENERAL RAILWAY SIGNAL COMPANY railways, but this system having developed many serious defects, its inventors devised and in 1891 installed the first electro-pneumatic plant at the Chicago & Northern Pacific Drawbridge, Chicago. In the following ten years, there were ordered — up to June 1, 1900 — fifty-four electro- pneumatic plants, having 1,864 levers, for use on thirteen railways. It was felt at this time that while power interlock- ing had been proven to be usable with advantage in a few important situations, it fell far short of accomplishing all that was desired and required of it by the railways, and it was even then believed by some engineers that owing to certain defects and limitations inherent in the electro-pneumatic principle itself, some safer, more reliable and economical system would have to be developed before power interlocking could, with wisdom, be more generally employed. Just at this time (May, 1900) a company was formed to develop and exploit the electric interlocking patents now owned by the General Railway Signal Company and embody- ing the now well-known "dynamic indication" principle. In 1901 this Company put in service its first electric interlocking plant employing the dynamic indication, at Eau Claire, Wis., on the C. St. P. M. & 0. R'y. As might have been expected, in view of the newness of the idea, and of the Company exploit- ing it in opposition to an old-established and rich competitor, its progress was slow; but, the idea being right, its progress has been steady and sure, with the result that in the eleven years since its first plant went into service, it has furnished for use on eighty-three railways in thirty-five States and Provinces of the United States and Canada, 440 of these plants, having 21,370 levers. In the sixteen years from the installation of the first commercial pneumatic machine, during which time no competitive power interlocking machine was on the market, the average annual sales were four and five-tenths machines and 147 levers In the eleven years following the installation of the first commercial dynamic indicating electric interlock- ing machine, and in competition with all other types of power interlocking, our average annual sales have been forty machines and 1,943 levers. With but few exceptions, American railways requiring DOwer interlocking now exclu- sively specify the "all electric,' .and while the success achieved with our "dynamic indication" system has led a number of ELECTRIC INTERLOCKING HAJTOBOOK companies to devise and offer electric systems, it is believed conservative to state that much more than 90 per cent, of all the electric interlocking in use in the United States is of our manufacture. A more exact statement of percentage cannot be given for the reason that, so 'far as we have been able to ascertain, other makers of power interlocking plants have not in recent years seen fit to give publicity to the num- ber of power plants and power levers installed by them, though prior to our advent in this field such statements were fre- quently published. It can, however, be positively stated that more of our electric plants and more electric levers have been installed on American railways in this past ten years than of all other types of power interlocking in the past twenty- eight years. An evolution so rapid, extensive and radical as this cannot fail to suggest an inquiry into its causes and what bearing they may or should have upon the interlocking practice of the future. During the annual meeting of the Railway Signal Associa- tion at Buffalo in October, 1901, one of the principal questions discussed was, "At what leverage is it economical to install power interlocking rather than mechanical." The consensus of opinion then seemed to be that power plants might be economically used where and only where, on account of the size of the machine or density of traffic or for any other reason, more levermen would be required to operate a mechanical than a power machine. At that time the writer hazarded the opinion that in the course of time mere size of plant and density of traffic would cease to be generally regarded as the sole or even as very vital factors in arriving at a choice between power and mechanical interlockings ; that signalmen who were at that time obliged to compare the advantages of mechanical interlocking v/ith those of the only power interlocking with which they then had experience, the electro-pneumatic, might reasonably be expected to change their views very materially when they came to be familiar with the advantages of "all electric ' ' interlocking. How far this forecast, which was then regarded by many able, experienced signalmen as visionary, was warranted may be judged by an examination of tables in this handbook showing hundreds of small and medium sized electric interlocking plants installed by us in the decade that 8 GENERAL RAILWAY SIGNAL COMPANY has elapsed since then, thus affording evidence that not only is electric interlocking rapidly displacing all other types of power interlocking but that it is being largely and increasingly used where formerly nothing but mechanical interlocking would have been considered. The writer believes now as he believed ten years ago that certain of the important reasons for this change are found in the following facts: Entirely aside from considerations of economical operation that obviously demand the usage of power interlocking at all points where more than one leverman would be required for the operation of a mechanical plant, or where train movements are so numerous as to make the operation of such a plant too great a physical strain upon the operator, there are other and equally important features to be considered with respect to every proposed new interlocking, chief of which is the fact that no purely mechanical interlocking ever devised is any- where near so safe as is the dynamic indicating electric inter- locking. In spite of the now general recognition of this fact, it must be remembered that it was only as the electric inter- locking came to be commonly used and its safety features to be compared with those of straight mechanical interlocking that the defects and dangers of the latter became emphasized by the contrast. Thus, beginning about ten years ago, the realization of this fact by skilled signalmen led them, at first slowly but as time has gone on more and more rapidly, to one of two practices, viz: the use, on the one hand, of electric interlocking, pure and simple, or, on the other, adding to mechanical interlocking all sorts of electrical apparatus and circuits. Where the latter expedient is adopted, the resultant composite plant requires a maintainer combining the experience of a mechanic and of an electrician, and such men are not numerous. Fifteen years ago the number of young men who had even a rudimentary knowledge of electrics was small; but — owing to the enormously increased employment of elec- tricity in telegraphy, telephony, lighting, manufacturing and transportation; to the institution of simple courses in elec- tricity in trade, industrial and correspondence schools ; and to the fact that it is easier and takes much less time to acquire a usable working knowledge of electrics than to become a fairly skilled mechanic — most railways now find it possible to procure, at the prevailing wage rate, men capable of ELECTRIC INTERLOCKING HANDBOOK 9 maintaining electrical rather than mechanical installations — particularly since the automobile and kindred industries have created such an unprecedented demand, at high wages, for mechanics. Another fact having an important bearing on this phase of our subject is this : American block signal practice, Uke its interlocking practice, was originally copied from the F^uglish, who employed the manual system. In block signaling, as was the case in interlocking, the American demand for labor saving devices early led to the invention of power operated automatic block signals, the first of which to be employed on a considerable scale were of the pneumatic type. Now, in automatic block signaling, as in interlocking, the electric is almost entirely supplanting the electro-pneumatic, and few, if any, American railways are now considering anything but electric signals for new block work. Such signals are now used on upwards of 35,000 miles of American railway, and large additions are being made thereto annually. It will hardly be denied by any engineer skilled in signaling that every interlocking plant located in automatic, electric, block signaled territory should be electric, since, if for no other reasons, it can be more simply installed, more economically maintained and more reliably operated than a mechanical or any other type of interlocking which would require the mixing in with the necessary electric block devices of other types of apparatus requiring maintainers and repairmen having needed training in two or more trades rather than in one. This is a consideration, which, quite apart from that of maximum safety, has led many railways to the installation of a great deal of electric interlocking in automatic block signaled dis- tricts and which is influencing them and others to take like action where automatic block signaling, though not in imme- diate prospect, may be put in within a few years. Thus it has come to pass that of the railway men who still feel that the mechanical interlocking when provided with various electrical adjuncts may be made to be almost if not quite as safe as the "all electric plant," more and more are coming to realize that simplicity, economy and reliability demand the usage of the electric interlocking in preference tx) any others, particularly as a mechanical plant, even when equipped with the most elaborate system of electrical adjuncts. 10 GENERAL RAILWAY SIGNAL COMPANY has not changed its nature but still remains a mechanical plant, subject to most of the operating difficulties inseparable from such a plant. Another situation that has largely influenced the adoption of electric interlocking is the following: Up to the time of the introduction of electric interlocking, it was the rule, rather than the exception, for American railways to operate from interlocking machines at ordinary crossings and junctions such switches as were within 700 to 800 feet of it, but not to operate or adequately signal more distant switches. Where any connection existed between such distant switches and the interlocking it was usually no more than that established by having an electric circuit controller on such a switch by means of which an electro-magnetically slotted distant signal alone was prevented from giving its proceed indication when the switch was open between it and the home signal. It was claimed by the railways, not without reason, that it was too difficult and costly, and in some instances impossible, to satisfactorily operate such switches from a single machine and that it would be the height of folly for them to install one or more additional machines merely for the sake of operating these switches, the interlocking of which would not have been at all considered at the moment except for their proximity to junctions or crossings they were obliged to interlock. Gradu- ally, however, for one or another reason, American practice is coming more and more approximate to that of England, where every main line switch on a passenger carrying road has to be properly signaled and interlocked, and coincident with and probably largely responsible for this changed attitude of the American railways is the now almost universal recognition of the fact that electric interlocking alone affords the means for successfully accomplishing this in the United States without excessive cost for both installation and operation. Many of our electric plants have for years satisfactorily operated switches, together with their allied signals, located from one to six thousand feet from the interlocking machine, some- times with tunnels or other obstructions to view, intervening between the interlocking station and the switches. In fact, as temperature changes, no matter how great or how sudden, do not in any degree affect the operation of our electric plants, they being absolutely free from such disorders as, in a ELECTRIC INTERLOCKING HANDBOOK 11 mechanical plant, occur because of contraction or expansion of parts connecting the interlocking levers with the switches and signals, and as the "dynamic indication" features and the "illuminated track diagrams" make it wholly unnecessary for the operator to see tracks, trains, switches, or signals — - there is absolutely no limit to the distance at which such switches and signals can be safely, reliably and expeditiously worked by means of our electric interlocking. As an illustration, it may be of interest to note here that by far the largest interlocking plant in the world, one of our dynamic indicating type, at the Grand Central Terminal of the N. Y. C. & H. R. R. R.,New York City, is operated most successfully under conditions where it is impos- sible to have any \'iew from the interlocking station of trains, tracks, switches, or signals. It would be possible, as is recognized by all who have closely observed and carefully studied the trend of American signal practice for a score or more of years, to cite almost number- less additional conditions each of which has had some part, big or little, in determining why it is that electric interlocking has been and is being increasingly installed in units varying all the way from four to four hundred levers; why it is used with equally satisfactory results at small junctions, yards and crossings where traffic is light ; at hundreds of points of medium traffic where machines of from sixteen to forty-neight levers are required and at the busiest and largest terminals ; but such a citation would be long, and after all, the whole matter can be briefly summed up by saying that the reasons why more of our dynamic indicating electric inter- locking machines have been installed in the last ten years than of all other types of power interlocking in the past twenty- eight years, and why they are being so largely employed where formerly only mechanical machines would have been considered are — that experience has fully demonstrated that wherever and under whatever conditions of traffic or climate our dynamic indicating electric system has been tried it has been found superior to every other type of interlocking, in safety, reliability, economy and rapidity of operation and in its adaptability to every present and prospective need of the user. For these reasons, the writer hazards the prediction that within the next ten years many important American railways will closely approximate to a condition where every 12 GENERAL RAILWAY SIGNAL COMPANY block signal and every interlocking machine, large and small, over long stretches of their main line will be controlled, operated and lighted by power supplied from central energy stations, and where, in consequence, mechanical or any other than electric interlocking will be almost as much a thing of the past as is the "horse car" on the street railways of to-day. To such readers as may be inclined to regard this forecast as wild or visionary, the writer suggests the perusal of the preface prepared by him for the 1902 Electric Interlocking Catalogue, and that this may be readily done, that preface is reprinted herein (see page 405). After noting the forecasts made in 1902 and finding that every claim therein advanced for the then newly introduced electric interlocking system has been fully met and that its general adoption has more than realized the most sanguine expectations then entertained for it — the reader may be less inclined to be over skeptical as to the pre- diction made for the coming decade. To meet the requirements of the many present and prospec- tive users of our dynamic indication electric interlocking, we have prepared this Handbook, wherein it is sought to furnish data that will be useful to all those seeking a true understanding of the dynamic indication principle, and to those who are required to prepare bills of material for, or to install, operate or maintain our electric interlocking. w. w. s. SECTION I G. R. S. ELECTRIC INTERLOCKING SYSTEM SETTING FORTH THE PRINCIPLES IN- VOLVED AND GIVING A BRIEF DE- SCRIPTION OF THE APPLIANCES USED G. R. S. ELECTRIC INTERLOCKING SYSTEM Requisites of a Properly Designed Interlocking System INTERLOCKED switch and signal appliances were first de- vised and used at junctions and terminal points for the pur- pose of reducing the number of men employed to go from switch to switch, throw them by hand and then give a hand sig- nal for the train to proceed over the route thus lined up. It was soon found that operating the switches and signals from a central point under the control of the levers in an interlocking machine greatly expedited the handling of traffic. By far the greatest accomplishment of interlocking, however, was the addition of an enormous factor of safety at such points to train operation.. Inherent in the system of mechanical interlocking which first was employed to control the switch and signal functions were certain recognized shortcomings as regards safety and facility of operation. Systems of power interlocking in the field prior to the intro- duction of the electric dynamic indication system, now owned and manufactured by the General Railway Signal Company, although giving increased facility of operation, did not and do not provide the greatest safety obtainable with this increased facility. The features of vital importance in considering the merits, of any system of power interlocking are those which are designed to give the greatest measure of safety together with facility of operation. The two features most important to safety are : First — The means provided to check the correspondence of movement between lever and the switch, signal, or other function controlled by it. Second — The means for preventing unauthorized move- ment of switches, signals, or other controlled functions. The reliability of the means by which the above protection is secured determines more than anything else the safety of a given system of interlocking. In fact, this is so vital that an interlocking plant without a thoroughly dependable system for insuring correspondence between its levers and the operated functions, and for preventing the unauthorized movements of such functions, is absolutely unsafe. The G. R. S. electric interlocking system fully meets the first important requirement of checking the correspondence of movement between lever and operated function by means of the dynamic indication, energy for which is furnished by a momentary dynamic current generated by the motor of the operated function itself when and only when the actual opera- tion of such function shall have been properly completed. Contrast this with systems employing A. C. or battery 16 GENER-\L. RAILWAY SIGNAL COMPANY indicatioii, in which the indication is secured from energy existent at the function prior to and during the movement of that function and dependent only on the closing of a single break in the indication circuit. The use of the dynamic current, generated by the momen- tum of the motor of the operated unit at one end of the circuit and so giving the desired indication at the lever at (he other end of. the circuity prevents the receipt of a feilse indication due to a -. ;.G Plant. Terminal, C. * N. W. R't Chicago between the wires of the circuit, and is, therefore, correct in principle. The unauthorized movement of switches or derails, or the improper clearing of the signals is prevented by a simple and effective method of cross protection, the basis for which is inherent in an electric interlocking system using d>Tiamic indication. It is a notable feature that the second require- ment is met by a means in which all the contacts required for this protection form a part of the operating circuit, thus check- ing their integrity at each operation. In order to fully consider the advantages of the G. R. S. ELECTRIC INTERLOCKING HANDBOOK 17 system of electric interlocking, its elements are described in more detail as outlined below. Elements of G. R. S. Electric Interlocking System A complete installation of the General Railway Signal Com- pany's electric interlocking system comprises the following elements : First — A source of power consisting of a storage battery with its charging unit. Fig. 2. Collinwood Ixterlockixg Plant. L. S. & M. S. R'r Second — Power control apparatus introduced between the source of power and the interlocking machine. Third — An interlocking machine with levers for the control of the switch and signal mechanisms. Fourth — Switch mechanisms, their operating and indicat- ing circuits. Fifth — Signal mechanisms, their operating and indicating circuits. Sixth — Means for the prevention of unauthorized move- ment of any function. In connection with such a system may be installed such accessories in the way of track circuits, detector locking, route locking, indicators, annunciators, etc., as may be de- sired at each individual installation. 18 GENERAL RAILWAY SIGNAL COMPANY Source of Power The source of power, from which the G. R. S. system of electric interlocking is operated, consists of a storage battery having an approximate working potential of 110 volts, this battery being charged by a power generating unit, which frequently is a generator driven by a small gasoline engine. Fig. 3. Model 2 Unit T.ever Type Interlocking Machi: Lake Street Interlocking Plant, Chicago Terminal, C & N. W. R't Power Control Apparatus Power is delivered to the interlocking machine under the control of protective apparatus, mounted on suitable switch- boards. Interlocking Machine The operation of each switch and signal function is controlled by levers, which with their respective locking tappets, indica- tion magnets and circuit controllers, are mounted in a common frame, the whole being known as an interlocking machine. Starting with the lever in either of its extreme positions, the stroke of the lever is divided into two movements. The first movement locks all levers conflicting with its new position and operates the function. The second and final movement ELECTRIC INTERLOCKING HANDBOOK 19 of the stroke releases such levers, hitherto locked, as do not conflict with its new position. Except in the reverse position of a signal lever, this final movement can be made after, and only after, the dynamic indication has been received certifying that the operated function has assumed a position correspond- ing with that of its lever. Switch Mechanism — Its Operating and Indicating Circuits Each switch and derail is thrown and locked by a switch and lock movement driven by a series wound direct current Fig. 4, Model 4 Switch Machine- Hi'ai B;;ii)^,k. Tower "A," Electric Division, X. Y. C. dc H. 11. 11. R. motor. Two wires are used for its control, one for the normal and the other for the reverse operation. These same wires are used for indicating purposes, the normal control wire being used for the reverse indication and the reverse control for the normal indication. The circuit is connected to main common at the switch location. The circuits for a switch are shown in simplified form in Fig. 5, the operating and indicating currents in the different diagrams being shown by the heavy lines. When the switch (normal position) is to be operated, the first movement of the stroke of the controlling lever carries it as far as the reverse indication position and permits current to flow as shown in Fig. 5B, which causes the mechanism to move the switch points to the reverse position and lock them in that position. When this movement has been completed the 20 GENERAL RAILWAY SIGNAL COMPANY Mam Common Sw itch Mechanis m n Battery Motor Armarure Normal Control &. Reverse Ind. Wire-, Reverse Control 3 & Normal Ind. Wire Lever FUll Nfbrmal A- AT REST- NO CURRENT FLOvy/JN& Switch Normal Hiniiih ^ 5^ 35 Lever at Ke.y/erse indiceffin^ Poaition •6- OPERATING m— 1 Svtfitch leaving i^ormal Position Hilil " — * — m — •^,^- t^S Lever at Reverse lndica+in(j Position C - INDICATING 1+ Switch Reverse HiliHIh ^ ^S ^uuv Lever Full Reverae 5wi4ch Reverb - AT REST - NO CURRENT FLOWING Fig. S. Simplified Circuits for Model 2 or Model 4 Switch Machine ELECTRIC INTERLOCKING HANDBOOK 21 circuit through the switch motor is automatically changed, disconnecting the motor from battery and connecting it in a closed circuit including the indication magnet (Fig. 5C) ; _ at the same time the armature terminals are reversed for indication purposes, this leaving the motor connections in proper position for the next operation. The motor (now a generator) with the momentum acquired during the operation of the switch movement, generates a momentary current which energizes Fig 6. Model 2 Switch Machines. Mayfair Interlocking Plant, C. & N. W. R'y the indication magnet, thus permitting the final movement of the lever to be completed (Fig. 5D). The operation of the lever and function from the reverse to the normal position is accomplished in the same manner. A useful feature, not usually obtainable in other power sys- tems, is that the movement of the switch points may be re- versed at any portion of their travel at will by the operator, and the lever movement completed upon the switch points assuming a position corresponding with that of the lever, irrespective of the direction of the first movement made by the lever. The complete switch operation and final movement of the 22 GENERAL RAILWAY SIGNAL COMPANY lever may be accomplished in from two to two and one-half seconds, the indication being practically instantaneous with the completion of the switch opwation. Signal Mechanism — Its Opera- ting AND Indicating Circuits The description of signal mechan- isms will be confined to the non- automatic, two position signal, as this will show the principles involved in aU types of motor driven signals now used in the system. This signal is operated by a mechanism in which the motor is directly connected to the semaphore s^ft through low reduction gearing. The signal is held at proceed during such time as its controlling lever is in the reverse position solely by a dense magnetic flux thrown across the air gap between the motor arma- ture and the field pole pieces (holding field pole surfaces are serrated; by cutting the windings on the holding field poles in series with the operating field windii]^. Each signal requires for its opera- tion and indication one vnre and a connection to the common return wire. A simplified circuit for this type of signal is shown in Fig. 8, the path taken by the operating, holding, and indicating current in the different dia- grams being shown by the heavy lines. Upon reversal of the controlling lever, the signal mechanism will receive current as shown in Fig. 8B, this causing it to move the blade to the proceed position. When the signal blade has assumed this position the circuit broker cuts in s^es ^ith the operating field and armature, the high-resistance holding field, thereby retaining the si^ial arm at proceed (Fig. 8C). The holding field windings have a high resistance, which reduces the cmrent to that employed for holding the signal at proceed. When the signal lever is placed in the normal indicating position, energy is cut oflF from the motor and the blade returns to the stop position by gra\aty, causing the signal mechanism and motor armature to revolve backward to their original Fig. 7. Model 2A Signal ELECTRIC INTERLOCKING HANDBOOK 23 R. N Control and Indication Signal Mtchaniirn f^ I , I Indication Lil Magnet Holdinto f Fielr) 2 1- Open r.eld Main Comnnon Motor ^^ Armature HHIlHI- Lever full normal 5iJ?nal at si'op A - AT REST - NO CURRENT ruOWING K. rs -ilililit— 1- L miiiif Ltver full reverse B - OPERATING Signal Icavinij stop positic i R. N liiiiiiicX H|l|l|l^ Lever full reverse ^ C - HOLDING Siijnal at proceed R. N 1 ililiiil-L- Lever at normal indicatini^ positioN R N D- INDICATING Signal at 10° Capprox) from stop position Lever full normal Signal at stop E- AT REST - NO CUI?RENT R-OWING Fig. 8. Simplified Circuits for Model 2A, Non-Automatic, Two Position Signal 24 GENERAL RAILWAY SIGNAL COMPANY position. Just as the blade reaches the stop position the action of the circuit breaker connects the motor armature and operating field into their original closed circuit (Fig. 8D), in which is included the indication magnet. Due to its acquired momentum the motor (now a generator) produces an indica- tion current in this circuit which permits the controlling lever to be moved to the full normal positi'^ /ig. 8E). It is universal practice to indica. . the signal lever in the normal position only, this insuring tliat the signal blade is in the stop position before releasing any of the switch levers in the route governed. No safety features are sacrificed if the signal fails to assume the proceed position upon reversal of its controlling lever. Dynamic Indication. The use of the dynamic indication as described above has the ftUoicing advantages : First — The indication is not secured from energy existent at the function prior to the movement of that function and dependent only on the closing of a single break in the indica- tion circuit, as is the case in A. C. and battery indication systems; but being a dynamic current generated by the mo- mentum of the motor, it can be secured only after actvxil opera-- tion of the function. Second — The energy for the indication is developed at one end of the circuit and the indication magnet is located at the other ; hence a cross between wires prevents indication, whereas in systems which use the battery in the interlocking station for indication a cross tends to cause indication. Third — No extra power is required for indication. Fourth — The indication current ceases automatically with the stopping of the motor and, therefore, no auxiliary devices or operations are necessary to cause it to cease. Fifth — No additional wires are required for indication. Sixth — The generated indication current automatically "snubs" the motor and causes it to stop without shock and without the use of buffers, springs, or auxiliary snubbing circuits. Seventh — The indicating circuit is automatically checked as to its integrity every time an indication is received, and being a closed circuit of low resistance around the motor, it shields the motor while at rest from all foreign currents. This inherently provides the foundation for the simple and effective cross protection system employed with the G. R. S. electric interlocking. Means for the Prevention of Unauthorized Function Movements The cross protection system prevents the unauthorized movement of any switch, signal, or other function due to energy improperly applied to its circuit through a cross between ELECTRIC INTERLOCKING HANDBOOK 25 wires, by cutting oflf current from the function in the event of such an occurrence. As explained under "Dynamic Indication," all functions are normally on a closed circuit of low resistance. Connected in each of these circuits is a small polarized relay through which all operating and indicating currents must pass in a direction to maintain the relay's <>ontact closed, while all currents from an unauthorized sourct^must pass in the opposite direction thus instantly opening ^.e contact. Through all these con- FiG. 9. MoD-EL 2A Signals. Chicago Terminal, C. & N. W. R't tacts in series is controlled the retaining magnet of an electro- mechanical circuit breaker, which is introduced into the power mains between the storage batteiy and the interlocking ma- chine. Hence, a cross onto the circuit of a function at rest, by opening the contact of its polarized relay, opens the electro- mechanical circuit breaker, cuts power off from the interlocking machine and thereby prevents any improper movement of the function. In a simple plant a single electro-mechanical circuit breaker is ordinarily installed, this preventing the movement of all functions at any time the circuit breaker may be open. Where traffic conditions warrant the increased expenditure, additional circuit breakers may be provided to permit of dividing the plant into as many sections as may be desired. 26 GENERAL RAILWAY SIGNAL COMPANY The design of the circuit breaker is such as to make it impos- sible for a leverman (thoughtlessly or through ignorance) to prevent it from performing its function. Cross Protection. The cross protection secured with tJu G. R. S. electric interlocking system has the following advantages J First — All contacts and connections depended upon fo^ cross protection are either on closed circuit or are used for opera- lion and indication, so that any failure of these contacts and connections, which would impair their usefulness as a crossi protective medium, also prevent operation and indication! Hence they are under a constant, automatic check without th^ use of any extra contrivances for this purpose. Second — Wire insulation is not depended upon for cros; protection. This system at certain installations has givei years of safe operation with wire, the insulation of which doe; not measure up to the usual standard. Third — The cross protective apparatus consists of the polar i ized relays and apparatus on the operating board ; no wire c! additional appliances are required outside of the station t ^ secure this protection other than the simple apparatus alread installed for the operation of the various functions. Fourth — The switch and signal motors, being of low resis ance, require a current of several amperes for their operation therefore, a cross to produce the operation of any functioi must be of very low resistance. Thus it will be seen that th system is not sensitive to the effect of crossed wires. Not- withstanding this fact, an efficient system of cross protectiot is provided in the G. R. S. system. i Conclusion i The comparative value of different systems of interlockiijj may be accurately determined by a consideration of but fovj essential factors. These four factors must be present in an* interlocking system to warrant its use. They are : Safet% Facility, Reliability, and Economy. Safety. 7 The factor first demanding consideration is that of safetj^ This essential of an interlocking system overshadows all othei considerations, and in the ideal system the safety must 6| absolute. The G. R. S. electric interlocking with dynamic indication provides a factor of safety that is the closest approxi- mation to the ideal known to those skilled in the signaling art This is verified by the statement made by a disinterested committee in an able report based on a study of various type' of power interlocking systems, presented to the Internationa' Congress of AQplication of Electricity held at Marseille^! France, in 1908, this statement being worded as follows: ' *'The safety of an interlocking plant is dependent solel^ ELECTRIC INTERLOCKING HANDBOOK 27 m the existence of a positive, reliable indication of corre- •ndence between the position of a lever and its controlled LCtion. * * * the Taylor (G. R. S.) system meets »n this requirement. In fact it insures absolute reliability indication by employing the motor as a means for generat- the required current as explained above — so that it is tain that the indication given cannot ever be due to^ de- ts in wiring. Then, this indication having been received the interlocking station, it establishes a control which is ■manently maintained by a source of energy located in ! station. Moreover this permanent control utilizes identi- ly the same circuit that is employed in the normal operation the function; in consequence, the circuit used is one that st be maintained in good, operative condition for each vement of the function. :t will therefore be seen that by virtue of this arrangement, » Taylor (G. R. S.) system insures permanency of indica- n ; tnat it is economical since it utilizes the operating source energy located in the station, and that it is absolutely stworthy since it is in no sense subject to any danger from ssed or grounded wires." cility. The facility offered by any given interlocking system depends gely upon : first, the rapidity of operation of the individual ictions, and second, its capabilities for permitting simulta- 3us operation of a number of functions. In such a system i amount of time required to move traffic is reduced to a nimum. By incorporating the above two features in the design of the >tem, the G. R. S. electric interlocking fully meets all Hands for facility of operation. This has been repeatedly Dven by the performance of the system at points where 3 traffic conditions have imposed the most exacting operating luirements. liability. The reliability of an interlocking system is primarily de- ndent upon the fundamental principle underlying its opera- n, and in general it may be said, without fear of contradic- n, that unless the principle is simple, it is not correct. The rrect principle having been adopted, the reliability of the stem then depends upon a proper design of each and every rt of the devices used to put the principle into practice. It is recognized that the principles of operation of the G. R. S. berlocking are correct, and the circuits simple to an extreme gree, no radical changes having been made in either since e introduction of the system. The parts of all apparatus are •ong and rugged, and capable of performing their functions thout undue wear and tear; furthermore, the design of all its of the apparatus has been so,. very carefully perfected 28 GENERAL RAILWAY SIGNAL COMPANY during some twelve years' experience that their form now represents the very best engineering practice. As an example of the system's reliability of operation, records published by an important railroad covering a period of one year show a total of 2,615,406 switch operations, in which tne number of imperfect operations were so few that they did not exceed one to every 186.814, and the total traffic detention for the year was only seventy and one-half minutes. Economy. Due to the correct design of the apparatus and resultant long life of same, the cost of renewals is practically negligible. This, together with the marked simplicity of the circuits, insures a cost of maintenance much less than in any other system of interlocking. The cost of operating also shows a corresponding economy, not only by the fewer number of men required for the operation of the power system as com- pared with the mechanical system, but also in the cost of power when compared \\ath other power systems. Carefully kept railroad records show that the power cost is but one cent for 300 to 400 switch and signal movements. A most minute analysis and extended description of the merits and advantages of any given system of interlocking fails to be convincing unless the truth of all the statements are thoroughly substantiated. That the above statements concerning the G. R. S. electric interlocking system must be true, is shown by the well nigh universal adoption of the system, both for lai^e and for small installations. Four hundred and forty installations have been made or are under contract on some eighty different railroads in all parts of the United States and Canada, a considerable num- ber of plants also having been installed in Europe. On the basis that one interlocking lever in use for one year equals one lever year, the G. R. S. system now shows a record of 110,000 lever years. The satisfactory operation of these installations, large and small, under widely varying conditions of both climate and traffic, is a most con\'incing demonstration that every demand for an interlocking system has been met in a most satisfactory manner by the G. R. S. electric interlocking. SECTION II G. R. S. ELECTRIC INTERLOCKING APPLIANCES GIVING A DESCRIPTION OF THE AP- PLIANCES USED AND THEIR METHOD OF OPERATION INTERLOCKING STATIONS The Interlocking Station THE interlocking station, from which the various switch and signal functions of the plant are operated, is usually a two-story building similar in appearance to those used at mechanical plants. The station does not require the same heavy construction used in mechanical work on account of the fact that the movement of the levers of the electric interlocking machine puts absolutely no strain on the building. It should be noted Fig. 10. Hackbnsack Dbaw Bridge Interlocking Station. Erie R. R. in this connection, however, that the frame building generally used in the earlier installations is of late years being largely supplanted by the more substantial brick or concrete structure. Size of the Building The station can be much smaller than that required for mechanical plants of the same number of functions due to the smaller size of the interlocking machine. The length of the building is usually determined by the size of the interlocking machine; the width, however, is generally in excess of that required for the machine, being increased to accommodate the table, lockers, etc., needed^ by the operator, and on the 32 GENERAL RAILWAY SIGNAL COMPANY sccono nooE. rtork Bench q6r-4-o- Cngi'ne Sfove ■ A'- 6' — *f- 3' 0'— «K- 3'- - Generdter 5-0 -1 Duct -fbrTiires to In+er locking Machine Fbner Board Relay Cabinei runer ooaro ) 5 to y iachihe i S 5.1 r Battery Cupboard "TTdcK side FIRST FLOOR. Fia. 11. Typical Plans of Interlocking Station fob Eighty Lever Machine ELECTRIC INTERLOCKING HAl^BOOK 33 larger installations to provide room for a train director and telegraph operator. When it is desired to have shops and storerooms located in the interlocking station, the machine ceases to be the determining factor in the size of the building, unless the additional space for these rooms is secured by using a three- story building as in the case of the Lake Street Station shown in Fig. 13. It is also true" that on small plants the location of the storage battery and power apparatus in the lower story of the station is apt to make it necessary for Fig. 12. South Englewood Ixterlockixg 6tatiox AND Power House, C. R. I. & P. R'y the building to have larger dimensions than those required for the interlocking machine. Arrangement of Apparatus The different methods of arranging the apparatus in the station is shown by Figs. 11, 13 and 15, which may be taken as typical of small, intermediate and large sized stations respectively. By reference to these illustrations it will be seen that the general practice is to locate the interlocking machine, the operating switchboard and such accessory appa- ratus as track diagrams, indicators, etc., on the top floor, the storage battery in a room by itself on the lower floor, and the charging apparatus on the same floor with the battery or in a building separate from the interlocking station. 34 GENERAL RAILWAY SIGNAL COMPANY 'T^iRS? >^ { Fig. 13. Plan of Lake Street Interlocking Station. Chicago Terminal, C. «fe N. W. R'y ELECTRIC INTERLOCKING HANDBOOK 35 Points to be Noted The design of the building should be such that the floors will be sufficiently rigid to properly support the machine. Wherever possible the general practice is to have the operat- ing room liberally supplied with windows to permit the operator to have a clear view of the tracks throughout the plant. It is highly desirable that the conduits or ducts provided for the runs of electrical conductors about the tower should be Fig. 14. Lake Street Interlocking Station. Terminal, C. & N. W. R'y Chicago of sufficient capacity to have 25 per cent, spare space after all wiring is in place. No special foundations are required for the apparatus used in an electric plant, except when the charging generator is driven by an engine, in which case a substantial foundation should be provided for the engine so that the building will not be subjected to any vibration during its operation. 36 GENE31A1. RAILWAY SIGNAL COMPANY O fc ^ ^ Sl^ ■ T i= c I (^ s B^ Z2 m POWER PLANTS AND SWITCHBOARDS Composition THE power equipment for the G. R. S. Electric Interlocking plants is usually composed of a storage battery, suitable means for charging the battery, a power switchboard and an operating switchboard. Fig. 16. Interlocking Battery (400 Ampere Hours) Installed ox Battery Racks Location The location of the units which compose the power plant varies considerably on different installations. The operating switchboard is always located in the operating room, being placed whenever possible in such a position that its meters and indicating lamp are in full view of the leverman when manipulating the levers of the machine. The storage battery is ordinarily located on the first floor of the interlocking station. The power switchboard and charging apparatus at many installations are placed in a room adjacent to that occu- pied by the battery, although building restrictions or the need of space for workrooms or offices often make it necessary to house this apparatus in a building separate from the inter- locking station. 38 GENERAL RAILWAY SIGNAL COMPANY Batteries The interlocking battery usually consists of one set of storage cells having a potential of 110 volts. A second or duplicate battery is furnished on a few of the larger installa- tions to insure sufficient power for any possible emergency. Fig, 17. Interlocking Battery (120 Ampere Hours) Installed in Battery Cupboard The capacity of the battery used should be based on the num- ber of function movements between battery charges and the current used for all auxiliary apparatus. The battery as usually installed comprises fifty-five lead type storage cells. When long runs of conductors between the battery and interlocking machine are necessary, one or more cells are sometimes added to the battery to compensate for the voltage drop which occurs in the conductors when- ever several switch functions are operated at the same time. ELECTRIC INTERLOCKING HANDBOOK This may also be taken care of by using wires of larger carry- ing capacity than would otherwise be necessary. Low voltage batteries are frequently installed to operate annunciators, indicators, relays and electric locks, and occa- sionally to serve the track circuits of the interlocking plant. Operating the relays, indicators, etc., from a low voltage battery usually proves more economical than to take current for that purpose from the main battery. Charging Apparatus The charging of the battery is generally accomplished by means of a shunt wound generator driven by an electric motor or gasoline engine. The generator should be capable of de- FiG. 18. G.R. S. D.C. Generator livering the desired current at any voltage from 110 to 160, the current output being determined by the charging rate recommended for the batteries installed. In [the event of the generator being used to supply current for lighting, either regularly or in case of emergency, the additional capacity required for the purpose should not be overlooked. When the generator is located at some distance from the battery it is necessary to take care of the voltage drop due to the resistance of the charging circuit, either by increasing the size of the conductors or by using a generator having a higher voltage rating. Whenever current of suitable voltage and from a reli- able source can be secured at reasonable rates, its use is rec- ommended. The motor-driven generator, referred to above, is usable with either alternating or direct current, the generator being shaft or belt connected to the motor as proves most 40 GENERAL RAILWAY SIGNAL COMPANY convenient. If the current supply is direct, a charging rheostat can be used for the battery charging, or if alternating, a rectifier employed. Charging rheostats, having no moving parts, are the simplest and mostreliable of the different types of apparatus which can be used in this work. They are, however, very much less efficient than other battery charging devices, and therefore should not be used when the cost of power is an item to be considered. Motor generator sets are compact, reliable and, furthermore, highly efficient. When used on this type of work, they can Fig. 19. G.R.S. D. C.-D.C. Motor Generator Set be designed for operation on voltages as high as 550, the lower voltages, however, being recommended as most satis- factory from the maintenance standpoint. Power Switchboard The power switchboard most frequently furnished (Fig. 20) is arranged to control the charging of one set of storage batteries from an engine driven generator, and in conjunction with the operating board to control the power delivered to the interlocking machine. It may be placed in any accessible position in the power house, convenience in making the runs of electrical conductors between the power board, the charging apparatus and ^ the battery being considered. The size and arrangement of the power board for different installations- -is determined by the method of charging the ELECTRIC INTERLOCKING HANDBOOK 41 batteries, the number of sets and voltage of each battery, and whether or not the board is to control any electric lighting which may be installed at the plant. If a motor generator set is to be controlled an additional panel for its starting device can be mounted on the switchboard frame. When the track circuits in the plant are operated from ■f Fig. 20. Standard Power Switchboard for One Generator AND One 110 Volt Battery storage batteries or from transformers located in the interlocking station, it is customary to serve these track circuits through switches on the power board. On the . switchboard shown in Fig. 20 are mounted a no-voltage, reverse-current circuit breaker, a field rheostat, a voltmeter, an ammeter, suitable switches, and the necessary fuses. The no-voltage, reverse-current circuit breaker, which is placed in the charging circuit between the generator and battery, is designed to open in case the voltage of the generator falls below that of the battery. By means of this arrangement the charging 42 GENERAL RAILWAY SIGNAL COMPANY of the battery can be accomplished without the constant atten- tion of the maintainer, this permitting inspections to be made at such intervals as may be most convenient. Fig. 21. Power and Distributing Switchboards and Motor Generator Sets. Lake Street Interlocking Plant, Chicago Terminal, C. & N. W. R't The rheostat connected in series with the generator field permits the generator voltage to be accurately regulated. The voltmeter and ammeter are arranged to give readings on the charging or discharging circuits as desired. The simplified diagram (Fig. 22) shows the principles of the circuits used in connection with this board and clearly ELECTRIC INTERLOCKING HANDBOOK 43 Power Switch Board Gen. armaturc 6en. field ^No vni - © Rheostat No VOLTAGE REVERSE CUR- RENT CIRCUIT BREAKER Main switch A To operating BOAwe - + no Volt BAttitRY ■^I'H'I'H'H 5 "lb OPERATmG BOARD Fig. 22. Simplified Circuits for Power Switchboard Fig. 23. Operating Room at Oregon Slough Draw Bridge. N. P. R'y Combination power and operating switchboard at extreme left. 44 GENERAL RAILWAY SIGNAL COMPANY Fig. 24 ^ Fig. 25 Standard Operating Switchboari. ELECTRIC INTERLOCKING HANDBOOK 45 illustrates the functions of the various devices essential to the power control. Operating Switchboard The operating switchboard shown in Figs. 24 and 25 is typical of those furnished where all functions in the plant are to be controlled through a single circuit breaker. When the plant is sectionalized the board must be equipped with addi- tional circuit breakers, one being required for each section. The apparatus mounted on the Doard illustrated consists of the cross protection circuit breaker with its indicating red lamp, a polarized relay, a ground lamp and switch, a volt- meter and an ammeter. A panel for lighting switches can be bolted to the switchboard frame when it is desired to control the lighting from this point. Operating Switch Board Interlocking Machine 1 Circuit Breaker , 1 j F-OM Power i 3^ 1 Positive Buss • BOAAO , 1 p <^''' ^"^^^^-^ u* [ frio. Buss 1 -—^ 1 Polarized Relay Contacts! i UU\ 1 x.^ zV 1 _ _I From Power \ Common Board | 6.'-'' ^"-"^ Fig. 26. Simplified Circuits for Opehatixg Switchboard Lettering of the cross protection circuit breaker contacts corresponds with the lettering used in Figs. 64 and 66. The cross protection circuit breaker, introduced into the power mains leading to the interlocking machine, is so controlled that in the event of current being improperly applied to the circuit of any function at rest, the circuit breaker will open and cut all power off from the system. The red lamp is arranged to be lighted at this time to call the leverman's atten- tion to the fact that the circuit breaker has opened. The design of the circuit breaker and its cover is such that it cannot be prevented from opening should a cross occur, nor can it be restored to its operating position except by means of the restoring handle. The simplified circuit (Fig. 26), in which is included only the apparatus essential to the circuit breaker control, shows the retaining magnet of the circuit breaker controlled through the polarized relay on the switchboard and those on the inter- locking machine in such a manner, that, should any of them reverse their position, the circuit breaker will immediately open. 46 GEISTERAL RAILWAY SIGNAL COMPANY The polarized relay on the switchboard is to guard against the effects of an accidental cross between the positive and indication buss bars on the interlocking machine, the relay operating in the same manner as the polarized relays which protect the various switch and signal functions. By means of the ground lamp and switch, the plant may be tested for positive and negative grounds. The voltmeter indicates the battery voltage at the terminals of the interlocking machine. The ammeter shows the current taken by the various func- tions when they are being operated. By observing this current reading the operating conditions of each function can be determined. This is particularly true of the switch functions, the need of oiling or adjustment being readily detected from the abnormal amount of current or length of time required for their operation. ELECTRIC INTERLOCKING MACHINES Interlocking Machine Control THE interlocking machine used with the G. R. S. system controls the movement of switch and signal functions through the medium of suitably interlocked levers, which with their guides, indication magnets and circuit controllers, are mounted in the common frame as shown in Fig. 27. General practice is to furnish an individual lever for each signal LAMP CASE riNOICATION [SELECTOR INO.MACNET SAFFTY HAONET LOCKING PLATES Fig. 27. Cross Section of Model 2 Unit Lever Type Interlocking Machine arm and for each switch function, except where two switches are to be operated together, in which case their levers are rigidly connected and operated as a unit. The design of the machine and the controlling circuits is such that the following features essential to safe operation are afforded : First — No lever can be moved from a given position if any other lever, mechanically interlocked therewith, is in such a 48 GENERAL RAILWAY SIGNAL COMPANY position that its controlled function will conflict with the function to be moved. Furthermore, due to the mechanical locking being of the preliminary type, before the given lever can be moved from its position, all these conflicting levers will be locked against movement until such time as it is proper for them to be released. Fig. 28. Four Hundred Lever* Interlocking Machine, Model 2 Unit Lever Type. Grand Central Terminal, Tower "A," N. Y. C. & H. R. R. K Second — The full movement of any switch lever cannot be completed until the controlled function has moved to, and been locked in, the position corresponding with that of the lever. In the case of a signal lever this correspondence of position is required only on the normal movement of the lever, which can be completed only after the signal arm has assumed the stop position. ELECTRIC INTERLOCKING HANDBOOK 49 Third — Each function when in a position of rest is pro- tected against any unauthorized operation" which might other- wise be accomplished through current being wrongfully applied to its controlling circuits. In explaining the operation of the lever, its movement is considered as being divided into three parts, the prelimi- nary, intermediate and final. In order that the reader may not be confused on account of the lever operation having previously been described as being performed in two move- ments (page 18), it is desired to point out that the pre- FiG. 29. Model 2 Uxit Lever Type Interlockixg Machine. Collin- wooD Interlocking Plant, L. 3. & M. S. R'y. (See Fig. 32) liminary and intermediate part usually constitute one contin- uous movement, it being necessary to separate them, however, when considering the detail operation of the lever. The following description is based on the operation of the switch lever. Each of these levers is provided with a cam slot, by means of which intermittent motion is transmitted to its respective tappet bar and thence to the cross locking. In Fig. 30 the dotted circles 1 to 5 in the cam slot indicate the positions of the locking tappet roller which correspond with the like numbered position of contact block Z. In the pre- liminary movement of the lever from position 1 to 2, the locking tappet is moved through one-half of its stroke, this movement locking all levers which conflict with the new 50 GENERAL RAILWAY SIGNAL COMPANY position of the lever in question ; in this movement no change whatsoever is made in the operating circuits. During the intermediate part of the travel from positions 2 to 4, the tappet bar remains stationary and the contact block Z is moved out of engagement with springs YY and into contact with springs XX as shown in Fig. 31, this setting up the circuits for the operation of the function. The lever is held at this point, (position 4), through the mechanical design of the lever proper, until such time as the function having moved to a correspond- ing position, generates the dynamic indication current which effects the release of the lever and permits its movement to position 5. During this final movement from position 4 to 5, the stroke of the locking tappet is completed, thereby unlocking all levers which do not conflict with the new position of the operated lever. The method by which the lever is prevented from completing its stroke, until the controlled function has moved to a corre- sponding position and has sent in its indication, is illustrated by the following : . in moving from positions 1 to 2 projection M on the lever coming against projection K on latch L, causes the latch to assume the position shown in Fig. 31. This brings projection J on latch L into the path of tooth' Q on the lever. In moving from position 2 to 4, tooth Q engages with cam N, rotating it to the position shown in Fig. 31. As it passes the central position (shown dotted in Fig. 31) it comes in contact with dog P which is forced under latch L, thereby locking the latch L in the position assumed. The lever is stopped at position 4 by tooth Q coming against projection J on latch L as previously explained. The indication current, bv flowing through magnet I, lifts armature T which causes plunger R to strike dog P and trip it out from under latch L. The latch L then drops to the position shown in Fig. 30, thereby releasing the lever and permitting its final movement to be accomplished. The movement of the lever from reverse to normal is per- formed in a similar manner to that described above. Atten- tion is called to the fact that once the lever has been moved to, or beyond, position 3, it can neither be moved forward beyond position 4 nor back beyond position 2 without the receipt of an indication. The movement of the signal lever is identical with that of the switch lever except that no electrical indi- csition is required during the reverse movement, the lever not being checked at position 4 due to a change in the design of dog P, which is mechanically tripped at this point from under latch L by cam N. The mechanical locking insures that before a signal can be given for any route, that all switch and derail functions in the route are thrown to the proper posi- tions and locked in that position, and that all opposing signals are in the stop position. No changes can be made in the position of any of these functions until the lever, controlling ELECTRIC INTERLOCKING HANDBOOK 51 PP 52 GENERAL RAILWAY SIGNAL COMPANY ELECTRIC INTERLOCKING HANDBOOK 53 the signal displayed at proceed, has been replaced to its full normal position. The various functions are protected against unauthorized movement by means of the cross protection system, as de- scribed on page 89, the individual polarized relays which furnish this protection being mounted on the terminal board of the interlocking machine. All lever contacts which form a part of this cross protection scheme are used in the operation of the function, and hence are checked as to their integrity with every complete operation. Model 2 Unit Lever Type Interlocking Machine The description of the interlocking machine following is based on the Model 2 Unit Lever Type (Fig. 27) which is considered the standard machine. This machine is a development of the Model 2, still widely used, a cross section of this being illus- trated by Fig. 137. Modifications of the Unit Lever Type machine are shown by Figs. 32 and 138, the latter being furnished when more contacts are required for supplementary circuits than can be secured on the regular lever circuit con- troller. The standard machine essentially comprises the frame, the levers with their guides, indication magnets and circuit con- trollers, the locking plates and locking, the terminal board, and the machine cabinet. Frame. " . The frame work, which consists of a bed, supporting legs and brackets, is substantially constructed, thereby insuring that all inter-related mechanical parts are maintained in their proper relative positions. For machines having a capacity up tojorty-eight lever spaces, the bed is cast in one unit. Machines of* over forty-eight levers are made up of various combinations of beds bolted together to give the required lever spaces. Locking Plates and Locking. The locking plates are securely attached to the front of the machine frame, being furnished in tiers to a maximum of three, the number depending upon the amount of locking required at each individual plant. A fourth tier can be furnished when necessary by using a special form of leg, which has sufficient height to accommodate the extra tier of plates. The locking plates are designed with vertical and horizontal slots, the locking tappets, one of which is attached to each lever, being fitted in the vertical slot directly beneath its respective lever. Movement is transmitted from the lever through the medium of the tappets to the cross locking, which slides back and forth in the horizontal slots of the locking plates. The dogs used in the cross locking can be furnished screwed or riveted to the locking strips, as desired. 54 GENERAL RAILWAY SIGNAL COMPANY .. 8 ^ t^ 05 •i r-l rH 1 1 a lO t^ ^ 19-(1 15-(1 17-(1 21-(2 15 15 ^ 1 V > ^ d ^ OJ u d s ;<3 • • • s • OS ■ t-^ t^ P O w ;?; 0) ■<1< lO «0t^0005O.-l(NC0 Tj< I T_ 7 00 0> O i-l IN M . o T-l t-( 1—1 1— t '"' o ^ >-< 00 o 1 1 o ^— s A K^ •* .o S J. w . . . . ^ • • a> > ■ ■ ii > 2 . !^ S" !- t^ oT ^ r- r-( o 1 ^ ' J^ ^ 1 1 o ^ Q(c-^ "5 P ■ ^ Jc i-H 05 —1 . (M t-t (N rH . Sir* -^ ' /-v ^ JL ' ' ^ A A * 1 lO »o lo in lo c^ 1 ■^ Tji Tt< ■* -a' -^ -~^ -^ ■ ^_^ v_^ ~^ U^ ~fe~ A -' C4 M ■* US CO ELECTRIC INTERLOCKING HANDBOOK 55 1 1 II II II' n II II II H il H I I II II iT 56 GENERAL RAILWAY SIGNAL COMPANY Each tier of locking has eight of these horizontal slots, and each of . these slots is capable of accommodating f our lockii^ strips, thus giving this type of locking bed a large capacity as is indicated by the fact that the locking required for extremely large and complicated layouts has been readily accommodated in three tiers. In fact, it is a very rare occurrence that the fourth tier is ever required. By using locking of the vertical type no additional floor space is required beyond that ordinarily taken by the machine, Fig. 35. Uxtt Type Switch Lever Eqcipped WITH Lever Lock axd Lamp Case (See Fig. 141.) no matter how many tiers are provided. This type of locking also permits ready access for infection or cleaning, or making any changes which may be required. Levers. Each lever with its guide, indication magnet, controllers, etc., comprises a complete unit in the interlocking machine, the design being such that the unit may be removed or replaced in the machine without moving the lever tappet from the normal position or disturbing adjacent levers in any way. The lever guide is jointly supported by the top edge of the locking plates and a longitudinal bar fastened to the brackets, the ELECTRIC INTERLOCKING HANDBOOK 57 circuit controllers being screwed to two other bars which are supported by this same bracket. The circuit controller with which each lever is equipped can be provided with a maximum of five tiers of contacts, con- trolling five normal and five reverse independent circuits, which affords more contacts than are ordinarily desired for supple- mentary circuits. The space required for each unit is but two inches, this permitting the complete machine to occupy less space length- wise than other existing types of interlocking machines, either power or mechanical, having the same lever capacity. Lamp Case and Number Plate. The combined lamp case and number plate is mounted above each lever, its base being attached to a plate screwed to the top of the lever guide, and its top to the cabinet frame. The num- ber plate is designed to lie at an angle which renders it readily visible to the operator when manipulating the levers. Bulbs and sockets are furnished only for such levers as may be specified, generally being used in conjunction with some type of electric locking to give an indication as to whether the lever may be moved or not. If desired, a double lamp case can be furnished to give two separate indications. Terminal Board. The slate terminal board is securely attached to the brackets on the rear of the machine On this board are mounted the switch and signal buss bars, the individual polarized relays, fuses for the operating circuits, and the terminal posts for all wires which form a part of any of the interlocking machine circuits. The wires running from the binding posts to the various contacts, etc., in the machine are made up as formed leads, thus presenting a neat and uniform appearance ; it also simplifies any "connecting up " incidental to the field installa- tion of additional levers to the machine. All fuses and terminal posts on the board are located directly beneath their respective levers, the terminal posts being lettered in correspondence with the circuit plan to indicate the wires which are to be attached to each post. Polarized Relay. The polarized relay which is illustrated by Fig. 36 is mounted on the terminal board directly beneath its lever. It is provided with a soft iron core which lies lengthwise between the poles of a permanent magnet, the design being such that current passing in one direction through a winding on the soft iron core, tends to hold the relay armature normal and contact closed, while current in the opposite direction imme- diately reverses the armature and thereby causes the contact to open. An extension of the armature is provided for con- 58 GENERAL RAILWAY SIGNAL COMPANY venience in replacing it to the normal position should it for any cause be reversed. Indication Selectors. The indication selectors, one of which is used in connec- tion with each switch function, are mounted on a shelf sup- ported by a bracket on the rear of the interlocking machine. The selector is simple in design, consisting of two electro niagnets and a contacting armature which throws in one direction when the lever is reversed and in the other when the lever is put normal. Fig. 36. PoIiABIZEd Relay Interlocking Machine Accessories Lever Locks. The electric lever lock, illustrated by Fig. 35, may be applied to any lever in the machine, its winding being designed for operation on direct or alternating current. The lock is designed to be moimted on the top of the lever guide, locking the lever in any required position by means of a solenoid plunger, which, when the lock is de-enei^ized, drops into a notch cut on the top of the lever. These notches may be arranged so that the lever will be locked in any position as required by the electric locking circuits used at the plant. The circuit for the lock coil is broken through a contact spring actuated by the lever latch, the lock therefore not consuming energy except when lever is to be moved. iiechanical Time Release. The mechanical time release furnished with the G. R. S. interlocking is illustrated by Fig. 37, and the method of its application to the machine by Fig. 38. It is used in connec- tion with electric locking circuits to effect the release of a route in case of emergency, this being accomplished by manipu- lating the release to its fuU reverse position, at which point a contact is closed to pick up a stick relay, energize a lever lock, etc. The first movement of the device towards the reverse ELECTRIC INTERLOCKING HANDBOOK 59 position, however, mechanically locks, in their given positions the levers controlling all functions in the route, this necessitat- ing that the release be returned to its normal position before the route can be changed. The operation of the release to the reverse position and back to the normal position affords a time interval of about two minutes. Fig. 38 Fig. 37 Mechanical Time Relbase SWITCH OPERATING MECHANISMS Switch Machine Control SWITCH and derail functions in the G. R. S. system are operated by s\^itch and lock movements, driven by series wound direct current motors. These switch mechanisms, each of which is under the con- trol of a lever in the interlocking machine, require for their operation two wires only, one being used for the normal and the other for the reverse operation. These same wires are used for indicating purposes, the normal control wire being used for the reverse indication and the reverse control for the normal indication. The circuit is connected to main common at the switch location. When the lever is moved to a position to cause the operation of the switch mechanism (see dotted position of lever con- tacts in Fig. 39), current is taken from the positive buss bar through the safety magnet, indication selector, lever contacts and the control wire, through the switch motor and to common. This causes the desired movement of the switch machine, which performs the following functions in the order given : First — The detector bar is raised and the switch unlocked, Second — The switch points thrown. Third — The switch points locked and the bar lowered, Fourth and Lastly — Current is cut off from the motor, and the terminals of the motor armature reversed for indication purposes, this leaving the motor properly connected for the next movement. . . The motor is now on a closed circuit which includes the indication magnet. Due to the momentum acquired during the switch operation, the motor armature continues on several revolutions for the generation of the momentary current which energizes the indication magnet and thereby permits the final movement of the lever to be completed. The operation of the switch machine in the opposite direc- tion is accomplished in the same manner as described above. The changing of the motor connections at the end of the switch operation is effected by the mechanical shifting of the contact olock in the pole changer (Figs. 42 and 46). In addition to being mechanically operated, this contact block is under the control of two sets of solenoid magnets, so that should the switch fail to complete its movement the controlling lever may be shifted, and, through the energizing of one set of the magnets, cause the j)ole conger to set up the circuit for the operation of the switch in the opposite direction. This places the mechanism so under the control of the lever- man that should the switch points be blocked with snow, ice, etc., the points may be worked back and forth, frequently dislodging the obstruction, thereby permitting the desired movement of the switch to be completed. ELECTRIC INTERLOCKING HANDBOOK 61 ^im^ t1 m'W\ M, II o si toe 211 1-1 O ^^ rc ^A c S ©«.- S ^ O OQ c^ 3 '^ -(J K^ ;':3 o-i W)£ o^ 2 ^,-5 o ^ „, ,, 1 J t3 C S = OJ o "^^^^ O -u ^ c ^i m 3 O) ^ * 62 GENERAL RAILWAY SIGNAL COMPANY indication magnet with the indication magnet armature resting on its poles, some distance from the poles of the indication magnet. The safety magnet coils are so connected in the operating circuit that the whole operating current flows through them, hence any current flowing through the indica- tion magnet, due to a cross between the control wires of the function, cannot exceed the current through the safety magnet. The winding of the safety magnet is proportioned so that in conjunction with the above two features, the indication mag- net armature cannot be lifted by current resulting from a cross as stated above. Fig. 40. Model 2 Switch Machine. Buffalo Creek Inter- locking Plant, L. S. & M. S. R'y From the time when the lever is moved to the new operating position until the movement of the switch machine is com- pleted, the indication selector further insures against the pos- sible receipt of any improper indication, being so connected that the operating current will attract its armature and close the contact for the reverse indication only when the lever is moved reverse, and the contact for the normal indication when the lever is moved normal. It should be noted that both the indication selector and safety magnet coils are con- nected in series with the control circuit, therefore if the cir- cuit through them is not intact, operation of the function will be prevented. ^ When the motor operating circuit is opened by the action of the pole changer, after the switch has been locked in posi- ELECTRIC INTERLOCKING HANDBOOK 63 tion, current ceases to flow through the safety magnet. There- fore the armature of the indication magnet is no longer held down, this permitting the indication to be effected upon receipt of the dynamic current generated by the motor. The mechanism is now at rest protected against any unau- thorized movement in the same manner as before the con- trolling lever was reversed. Owing to the design of the operating circuits, the magnetic Fig. 41. Model 2 Switch Maciiixe. Ci.i\in\ mreet Interlockinx; Plant, Chicago Terminal, C. & N. W. R'y Spring attachment shown is furnished with Model 2 switch machine when detector bar is not installed. control of the pole changer prevents the switch from being moved by hand from the position occupied, except through breaking the operating circuits by some such means as re- moving the motor brushes. If this is done and the machine moved to a position not corresponding with that of its con- trolling lever, upon the replacement of the brushes, the switch will immediately assume its proper position. Manipulation of the pole changer by hand will not cause movement of the switch out of correspondence with its lever. 64 GENERAL. RAILWAY SIGNAL COMPANY Model 2 Switch Machine The Model 2 switch machine, illustrated by Fig. 43, con- sists of the motor, gearing, lock movement and the pole changer with its actuating movement. The gear frame and locking movement are securely bolted to a tie plate as shown, to which plate the stock rails are also securely attached, thus rigidly maintaining all parts of the s\^-itch machine in their proper relation to each other and to the rail. Movement is transmitted to the ^'arious switch parts by the motor through a train of spur gears. Fig. 42. Pole Cha>»gek fob Model 2 Switch 3Iachixe The locking plunger I and detector bar are actuated through the lock crank H and the dri\ing rod G, this latter being directly connected to the stud F on the main gear D,. It "vdU be seen that a train occupying the track, in preventing the initial movement of the detector bar, would make impossible the withdrawal of the lock plunger from the throw and lock rods, and therefore prevent any movement of the switch points. The switch points are thrown by the rod J and the cam crank E due to the stud F on the main gear engaging with the cam crank. The operation of the i>ole changer B is effected through the mediimi of the pole clmnger movement L by the last one- dghth inch movement of the lock plunger I after it has passed through the lock rod K (Fig. 146). ELECTRIC INTERLOCKING HANDBOOK 65 M N DETECTOR BAR CONNECTION Fig. 43. Model 2 Switch Machine A Motor H B Pole Changer Friction Clutch I C J I). Main Gear K D. Intermediate Gear L E Cam Crank M F Stud on Main Gear N G Driving Rod Lock Crank Lock Plunger Throw Rod Ix)ck Rod Pole Changer Movement Pole Changer Connecting Rod Detector Bar Driving Link Pin 66 GENERAL RAILWAY SIGNAL COMPANY I-' 1 •2 o ^ a a 1 6 a 6 1 r1 03 £ '« a . -^ If g 1 1 3 1 OJ Cl u bC bO (§ Ph H M _c ^c g o o ;4 a V fl > a C ^.y s o c P5 1 M J H 1 •-9 1 (a p 5 ^ oq o Q c^ cCC ;5'c5 s^'s^V '-C'-^' •^ t< ^ ^ ^ a. CQ ELECTRIC INTERLOCKING HANDBOOK 67 The design of the mechanism is such as to allow the switch motor A, due to its acquired momentum, to continue its rota- tion for the generation of the indication, which checks the speed of the motor and brings it to rest without shock. A friction clutch C is introduced into the connection between the switch motor and the main gear to relieve the switch mechanism from any injurious strain should it suddenly be brought to stop by an obstruction in the switch points. Model 4 Switch Machine The Model 4 switch machine shown in Fig. 44, is designed with all operating parts within one case, and is especially adapted for installation where clearances are limited. The Fio. 43. Model 4 Switch Machine. Noble Street Ixterlockinq Plant, Chicago Terminal, C. & N. W. R't case, which affords complete protection against the weather, provides a base plate for the mechanism, being bolted through the tie plate to the head block and the next tie back (Fig. 149). The operating parts consist of the motor A, a train of spur gears, the main or cam gear D, the pole changer M, the throw rod J and locking bar F. , . ^ ■, • The motor through the medium of the tram of gears drives the cam gear, from which gear the various parts of the switch machine are operated. , , , . , -, j ^ ^ The intermittent movement of the locking bar and detector bar is accomplished by the engagement of rollers on the locking bar with the cam slot on the upper side of the mam gear. Staggered locking is provided by the arrangement of the dogs on the locking bar, these dogs being placed so that after one dog has been withdrawn to release the lock rod, the switch points must be moved to the opposite position before the other dog can enter its slot in the lock rod. The throw rod is locked 68 GENERAL RAILWAY SIGNAL COMPANY in both extreme positions of the switch by a bolt operated from the cam movement. The switch points are thrown at the proper time by a roller on the lower side of the main gear engaging a jaw in the throw rod. The principles of the pole charter movement are essen- tially the same as in the Model 2 s\\atch machine, although the mechanical method of effecting this action is accomplished through the main gear movement and locking bar, instead of Fig. 46. Pole Chasgeb fob Model 4 Switch Machine Tripper arm X shown at the top of its vertical movement. through the pole changer movement and locking plunger as in the Model 2. Contact blocks S, and S.> are operated from tripper arm N which engages at the proper time \^dtb a cam either on the upper or lower surface of the main gear D. depending on the direction of travel of the mechanism. The tripper arm is placed in a position to engage with the proper cam only after the switch has been locked in position at the end of its move- ment. This is accomplished throi^h the medium of cranks Tj and Tj. a roller U on the latter working in a cam slot on the locking rod F,. The contact arm V (which corresponds with the commutator T on the Model 2 pole changer, Fig. 42) is operated by this same crank movement. ELECTRIC INTERLOCKING HANDBOOK 69 The cam gear is designed to permit a free run of the motor at the end of the operation of the mechanism for the purpose of generating a strong and positive indication current. A friction clutch, designed with large surfaces and lined with fibre, is provided to protect the mechanism from shock, should its movements be obstructed. A switch circuit controller can be furnished if desired, located within the mechanism case at the point indicated by letter 0. The operating part consists of a frame carrying contact fingers and a cylindrical commutator W upon which are mounted contact segments. As the switch is unlocked, a disengaging arm X with roller Y working in a cam slot on the locking bar F^, lowers the commutator out of engagement with the contact springs. During the movement of the switch points, the commutator is rotated on its axis through motion Fig. 47. Switch Circuit Controller for Model 4 Switch Machine transmitted from the switch points by means of a crank con- nection, a sector (not shown) and pinions Zj and Zg. After the points are locked in position the commutator is raised into engagement with the contact fingers by the engaging arm and cam slot movement. It will be seen that this control insures the switch points are in position and locked in position before the switch circuit controller can be closed. The maximum capacity of the controller is ten independent circuits, the con- tacts being adjustable in pairs to close as desired at the normal or reverse positions of the switch. The switch mechanism can be used right or left handed without change, as the lock and throw rods may be connected from either side. A double locking cage is furnished when the machine is to operate a double slip switch or movable point frog, thus avoiding the necessity of using a plunger lock with its special connections otherwise required for the second lock rod. All parts are assembled in the factory and tested before shipment under conditions approximating as nearly as possible the service to be given the machine after installation. MOTOR DRIVEN SIGNAL MECHANISMS MOTOR driven signals in the G. R. S. system of electric interiocking are operated by mechanisms in which a series wound motor is directly connected to the sema- phore shaft through the medium of low reduction gearing. No dash-pot or electro-mechanical slot is required for this type of signal. The mechanism is applicable for use as a high or dwarf signal. The mechanisms furnished are of two types : First, the non-automatic, which is entirely under the control of a lever in the interlocking machine. Generally speaking, this type is furnished for dwarf signals, and for such high signals as will at no time require track circuit control. Second, the semi-automatic, which is operated under the joint control of a lever in the interlocking machine and the track circuits in such sections of track as are governed by the signal arm. The semi-automatic mechanism is also furnished for non-automatic high signals when there is a possibility of the signal arm being controlled by track circuits at some future time, or in case it is desired to have uniformity in the type of mechanism throughout the installation. Either of the above types can be adapted for operation in two or three positions, upper or lower quadrant, and to give right or left hand indications as desired. In the two position non-automatic signals, but one wire besides the main common is required for its control, this wire being used both for operating and indicating purposes. When the signal is- to operate in three positions an additional control wire is required. In the case of semi-automatic control, an additional wire may or may not be required, depending entirely upon the arrangement of the track circuits in the route governed by the signal arm. Non-Automatic Signal Control The following description of the signal operation is based on the circuit shown in Fig. 48 which is for the control of the two position non-automatic signal mechanism. Upon reversal of the controlling lever current is taken from the positive buss bar through the lever contacts, the control wire, the operating field and armature of the signal motor, and thence to common through the various switch circuit controllers as required. This causes the movement of the blade from stop to the proceed position, upon the com- pletion of which movement circuit breaker contact JB opens and A closes, this connecting the holding field of the motor in series with the operating field and armature. The design of the pole pieces on which the holding field windings are mounted, is such that the magnetic flux, thrown across the air gap between the motor armature and the pole pieces, magnetically locks the armature against rotation and thereby retains the ELECTRIC INTERLOCKING HANDBOOK 71 Its??!.' -*^JL=!c:bfl ii iim -5 2 «« £ J-- to Jh ^j> •+3.t^ rt ?> 9^ o a fl +j OJ- ■ — 02 QJ — Q)'^ ra'aJ^ S o ^ S 3J ^^ .^ dj r^ sW 03 <^^ a .Stag's j^ Ota F^ ^ TO CQ "-"Tt O ^ "^ C 4 5; rt px 3??occ!c:P:3 f_ 4J « -tJ -^J O -IJ Ci'-i (D-TJ C +3 C (u i=! 2J c ® •43 OJ -73 'xj <^ Pud ^5 5^6 'O CO O) • i2 o R ■c«-52 •^ :2 +j T3 C fa OJ ^-^ ^H ^ « c-^ _2.2of3.S**-'c§<:35lC .2? 3 P<4J -tJ P* « -!-> 72 GENERAL RAILWAY SIGNAL COMPANY mechanism and brings it to rest without shock to any of its parts. In the case of the three position signal, operation from the zero degree position to the forty-five degree position is the same as described above. Operation from this point on to the ninety degree position is ordinarily dependent upon the signal in advance, it being necessary however that the controlling lever be reversed before movement of the mechanism can take place. The mechanism is held in its ninety degree position through the medium of the holding fields in the same manner as in the forty-five degree position. When the signal arm is re- turning from the ninety degree position and is to be held at the forty-five degree position, its movement is arrested at that point by short circuiting a " snubbing " winding on the motor (winding and contact not shown in Fig. 48), whibh causes a momentary current to flow in this winding, thereby bringing the mechanism parts to rest. The semaphore arm is retained in this position by current flowing through the retaining fields of the motor, as previously explained. Semi-Automatic Signal Control When it is desired to have the signal controlled semi-auto- matically, the operation differs from that described above in that the first fortj^ degree movement of the mechanism from the normal position does not affect the position of the signal arm, but puts under tension a set of coil springs which are strong enough to rotate the motor on the return movement with sufficient speed to generate the current for energizing the indication magnet on the lever. This preliminary move- ment of the mechanism is always under the control of the operating lever irrespective of whether the traqk circuit is occupied or not, the receipt of the indication therefore not requiring the restoration of the lever to the normal position simultaneous with the entrance of a train into the controlling track section. Any movement of the mechanism beyond this point, however, is dependent upon the track circuit being unoccupied. Referring to the circuit for the two position semi-auto- matic signal as shown in Fig. 49, it will be seen that upon reversal of the controlling lever current is taken from the positive buss bar through the lever contacts, the control wire, the signal motor operating field and armature and thence to common. This causes the operation of the mechanism through its preliminary forty degree movement to the zero degree position, at which point the mechanism will be held against the tension of the coil springs, in the event of the track circuit being occupied; this is accomplished by circuit breaker contact Bj opening and Ai closing which connects the holding fields in series with the operating fields and armature of the signal motor. Should the track circuit be unoccupied, the mechanism will not stop at this point but ELECTRIC INTERLOCKING HANDBOOK 73 ou. 2! O « 23J « g rt c c o ^•^^ (DC 43 bfi gS ^ o o o, O ;3, O I 0; OJ £ Q) ^0 CQ GO O S 2' O OTJ a; (U O 0) ♦I o c o w S Jj i-tl.w.J- g ^ c i'^ C5 S CXC fi ^^ o 1- 0} r^ --i5 5^ "5 o 2i O -M £ O C -43 -^pq O bX)« «^ p rt O O^ •sg; ^, O c3 c o ^•- OJ 0) =^ g - >;< 0) e 3 »- bJD-« ca C a; ;3 ^ C O SS.2 C3 O fl o V "'^ ^ 5J 5 ;jii (X2 « s -go -5 ^_ H CD 03 (U CO 7-3 ? O O ^ § 2i o^^ S fcJDC M ,000 11 CD ^^ 0-5 P 0) a> oj : ^ c5 3"fl .s ^o o fe^ eg g g -^ p airs oB^ 03 S q sis a> POOj:3.Sfl,-*^ .^ Fig. 63. Model 3 Solenoid Dwarf Signal Operating Mechanism . A I- A., Operating Coils Bi-B^ Holding Coils C Operating Contact D Indicating Contact E1-E2 Solenoid Plungers F Yoke G Operating Rod H Roller J Spare Contact to open with the first movement of the arm towards the pro- ceed position. The roller for the operating contact C is car- ried by an arm , which is raised by engagement with a collar on the operating rod, when the dwarf spectacle has assumed the proceed position. GENERAL. RAILWAY SIGNAL COMPAN^- CROSS PROTECTION APPARATUS Principles of G. R. S. Cross Protection THE G. R. S. cross protection system prevents the unau- thorized movement of any switch, signal, or other func- tion, in the event of current being improperly applied to its circuit, by the cutting off all energy from the function. As briefly outlined in the pages on the "G. R. S. Electric Interlocking System," it has been seen that all functions while at rest are normally on a closed circuit of low resistance ; that inserted in each of these circuits and located on the ter- minal board of the interlocking machine, is a polarized relay of very low resistance connected in such a manner that all currents, caused to flow through the circuit by the manipu- CiRCoiT BRt:A^cR A a + X 110 Volt ^=- Battcry -=. EntRGiZEO Control Hire: >> ?s^-^ POLARizto Relay FuNCTIOH AT RCST Function being operated Fig. 65. Simplified Circuit Showing the Principles of the G. R. S. Cross Protection System All functions when at rest are on closed circuit as shown by function C. All normal currents will flow through the polarized relay B in the direction indicated by the heavy arrows, but all currents due to a cross in the oppo- site direction as indicated by the dotted arrows. Hence current supplied through a cross X will open polarized relay B, which will cause circuit breaker A to open and thus cut current off the system. lation of the lever, must pass through the relay in a direction to maintain its contact closed, while all currents which may be applied through any other channel must pass through this relay in a direction to cause it to open its contact; and that this operation breaks the control circuit of the cross protec- tion circuit breaker, causing it to open and cut power off that section of the system affected, thereby preventing the unauthor- ized movement of the function. The principles involved will be made evident by reference to Fig. 65, from which circuit has been eliminated all detail connections, contacts, etc., only such parts being shown as are essential to the explanation. In Fig. 64 there is shown in full circuit detail all apparatus and contacts pertaining to a switch function, a signal function, 90 GENERAL RAILWAY SIGNAL COMPANY' [1 Q ix r£^ f m J -. Lai. P-^ — ; ■ 1 Q n: M < ■- z 8 "^ ELECTRIC INTERLOCKING HANDBOOK 91 and the system of cross protection. By tracing out these circuits it will be found that the circuit conditions as shown in Fig. 65 exist and afford the protection claimed. Operation of the Cross Protection Circuit Breaker The circuit breaker construction and its manipulation are clearly illustrated by Fig. 66, the position in Fig. 66C cor- responding with that of the circuit breaker in Fig. 64. The Various parts of the circuit breaker which make contact with each other are indicated by similar letters. It has been shown that current applied from an unauthor- ized source to the circuit of a function at rest, causes the polarized relay in that function's circuit to open its contact and interrupt the circuit through the retaining magnet of the cross protection circuit breaker. When this occurs the cir- cuit breaker armature is released and the Z contacts are opened, the armature falling to such a position (Fig. 66A) that it cannot be drawn up against the pole pieces by the magnetic pull which will be exerted when the retaining magnet is again energized through the restoration of the polarized relay armature. To inform the leverman that the circuit breaker is open, a red lamp is lighted by the closing of the Y contacts. With the circuit breaker open as in Fig. 66A, the positive and negative feeder wires between the battery and the inter- locking system are opened at the Z contacts, therefore the cross can have no effect. The polarized relay which had its armature reversed will identify the function affected and, upon the cause of the trouble being removed, the armature of this polarized relay will remain in its normal position, when re- placed by the operator. This will cause the retaining magnet of the cross protection circuit breaker to be energized, and, by raising the restoring handle to the position shown in Fig. 66B the circuit breaker armature is restored to its operating position where it will be retained by the circuit breaker magnet. This action closes the Z contacts, but at the same time opens the X contacts, through which contacts are also broken the positive and negative feeder wires, this preventing the appli- cation of current to all functions controlled by the circuit breaker until the restoring handle is returned to its normal position. The red light is extinguished when the circuit breaker armature is restored. Figs. 24 and 25 illustrate a typical operating switchboard, one view showing the cross protection circuit breaker exposed and the other with its cover in place. It will be noted that the only portion of the circuit breaker which is accessible to the leverman is the restoring handle projecting from the slot at the bottom of the cover. A shield attached to this handle closes this slot when the handle is in the normal position, thereby protecting the internal parts against manipulation in any way except by means of the restoring handle. , As 92 GENERAL RAILWAY SIGNAL COMPANY explained above, so long as the handle is held in a position to inteffere with the release of the contacts normally retained by the magnet (Fig. 66B), enogy is withheld firom all functions under the control of the circuit breaker. These features make the cross protection system fully effective at all times, even though force of circumstances may require its being temporarily under the charge of unskilled employees. When it is desired to retain such signals in the proceed position as may be occupying that position when the circuit breaks* opens, resistance units R and R^ (shown dotted in Fig. 64) are connected so as to bridge the X and Z contacts, these units pa*mitting the flow of an amount of current sufficient to hold a limited numb^* of signals at proceed. Their resistance is so high, howevo*, that the meclmnism requiring the least Fig. 67. Polabued Rei^t current for its operation cannot be put in motion if energ>^ should be applied to its circuit when the circuit breaker is open. The resistance units are shown in position on the operating switchboard in Fig. 24. , The Polarized Relays The polarized relay inserted in the indication circuit of each of the operated functions, and moimted on the terminal board of the interlocking machine, is shown in Fig. 67. The windings are so design^ that the armature of the relay for a switch, s^nal, etc., will reverse on about one-half the current required to just move that function of the same type which requires the least current for its operation. From this it will be seen that the windings of the polarized relays used with different types of functions have different resistances. On the switchboard there is shown in Fig. 24 a polarized rday similar to those mounted on the interlocking machine, the position of this relay in the circuit (Fig. 64) being indi- cated by the letter "A." This rday guards against crosses ELECTRIC INTERLOCKING HANDBOOK 93 between the buss bars on the interlocking machine, such as might be accidently caused by the maintainer's tools when *he is working about the machine. From the position of the relay in the circuit, it will be seen that any current reaching the indication buss bar through such a cross will flow in the direction opposite to that of the indication currents, this causing the relay to reverse its contact in the same manner as the polarized relays previously described. Since the relay on the switchboard is common to all circuits, its winding is designed to render it much less sensitive than those on the interlocking machine. Safeguards To show that the system in addition to being extremely simple, is also fully safeguarded, the following points are mentioned : First — The closed circuit principle is employed for all parts of the cross protection system. Second — All contacts or connections depended upon for protection against crosses are also used in operation and, hence, are checked as to their integrity every time a complete operation of a function is made. Third — The polarized relay contact, in addition to opening on a reversed direction of current, will also open upon loss of magnetism in the permanent magnet of the relay. Fourth — An open circuit in the polarized relay prevents indication. Sectionalizing of Plants In connection with a comparatively simple track layout, it is common practice to install only one cross protection circuit breaker, which prevents the movement of all functions during such time as it may be open. At busy plants having a large number of routes which can be used simultaneously, it may be considered undesirable to have the whole plant affected by derangement at a single point, in which case the plant may be divided into sections, the functions in each section being controlled through separate circuit breakers. This permits uninterrupted operation of traffic through the sections not directly affected. In addition to the cross protection circuit breakers required, it is necessary to install switchboard polarized relays and also common return wires for each section in the interlocking plant. The positive buss bar and indication buss bar must be divided to correspond with the sectional division of the functions. It is essential that there be no connections between the various buss bars or the common return wires, except where they join the energy mains from the battery, under the protection of their respective cross protection circuit breakers. There may be certain situations where conditions will warrant the additional expense of employing individual cross protection circuit breakers for each switch and each group of 94 GENERAL RAILWAY SIGNAL COMPANY signals. This would mean that a cross applied to a given switch, for example, would merely make that particular func- tion inoperative without interfering with any of the other- functions. The use of indi\'idual cross protection circuit breakers requires the running of a separate return wire for each of the functions or groups of functions concerned, and dispenses with the main common previously mentioned. The device (Fig. 68) employed for this purpose consists of a modified form of the regular polarized relay, provided with suitable contacts and a restoring handle. The contact pres- sure is increased over that of the regular polarized relay, at the same time retaining the relay's sensitiveness to reverse currents, the contacts are heavier in design, and the iron in the magnet is so distributed that a powerful magnetic blowout is obtained which effectually extinguishes any arc resulting from currents flowing through the contacts at the time of their opening. The principles involved in the making and breaking of the circuits, and in the restoration of the relay armature to the operating position after having been reversed, are similar to those of the cross protection circuit breaker pre\'iously de- scribed. The device, as installed, is enclosed in a sealed case (Fig. 69) to prevent any improper manipulation of the circuit breaker parts. This protective apparatus is mounted on the terminal board of the interlocking machine, occupying the same space as the regular polarized relay. The de\ice, which is exceedingly simple in construction, is in no way subjected to weather con- ditions and is much more accessible than if located rn the field at the various switches and signals, as is the ordinary practice with some systems employing individual cross pro- tection. „ ^ ^ Tests for Cross Protection It has previously been stated that all contacts and connec- tions depended upon for cross protection are under a constant automatic check during the regular operation of the different functions; therefore tests on the cross protection system are in no way requisite in the same sense tlmt tests are necessary' on switch points, to determine with what maximum opening the switch points can be locked. It is considered, however, that the satisfaction of having a working demonstration of the existence of the cross protection more than repays the slight trouble involved in making it one of the points to be checked up, on the regular inspection trip. The time chosen for conducting such a test should be when the voltage on the system is at the highest point attained in service. This will be when the interlocking battery is being charged, at which time the current will run up above 140 volts. The tests on the various switch functions may be secured by making a connection between the normal and reverse operat- ing wires on the pole changer. ELECTRIC INTERLOCKING HANDBOOK 95 Fig. 68. Individual Cross Protection Circuit Breaker Cover removed. Fig. 69. Individual Cross Protection Circuit Breaker 96 GENERAL RAILWAY SIGNAL COMPANY In testing signals, the necessary energy may be obtained at the nearest switch mechanism, since one of the switch control wires is always connected to battery positive (Fig. 64). The test should be made by connecting energy onto the signal control wire as near as possible to the signal motor, and if the signal circuit is connected to the common return wire through one or more swatch circuit controllers, the energy should be applied to this wire, care being taken to first open the connec- tion to the main common wire. Failure to open this connec- tion to common in all probability will result in blowing a f\ise in the switch circuit from which the energy is being taken for the test, since under these conditions a short circuit to the common return wire is created. Where the plant has been sectionalized, one or two functions in a given section should be crossed up with wires taking energy from each of the other sections. In case the functions in the various sections are widely separated, these crosses may be made between the binding posts in the terminal board of the interlocking machine, to avoid running a conductor long dis- tances over ground. This test will insure that the proper division of the functions was made at the time of installation, and that no undesirable connections have since been made. For the first test after an interlocking system has been installed it may be well to connect an adjustable resistance in the wires used in making the crosses, starting with the resist- ance all in and gradually cutting it down until the circuit breaker opens. For the periodical tests which some railway companies carry out this resistance is generally considered unnecessary. ACCESSORIES MODEL 3 FORM D SWITCH CIRCUIT CONTROLLERS Fig. 70. Model 3 Form D Switch Circuit Controller Two circuits, normal or reverse. Fig. 71. Model 3 Form D Switch Circuit Controller Two circuits normal and two reverse. Fig. 72. Model 3 Form D Switch Circuit Controller Four circuits normal and four reverse. 98 GENERAL RAILWAY SIGNAL COMPANY MODEL 5 FORM A SWITCH CIRCUIT CONTROLLER The Model 5 Form A switch circuit controller arranged for selecting signal circuits is shown by Figs. 73, 74 and 75. The operation of the contacts, which are forced open and forced closed, is effected through a cam movement, which causes all wear to come on heavy iron parts and not on the contacts. The contacts may be adjusted in pairs to make normal or reverse contact as required. One pair is adjusted by means of the screw jaw on the connecting rod and the other pair by means of the cam (Fig. 187), the parts after adjust- ment being positively locked against working loose. The contacts and binding posts are mounted on a vertical panel which gives convenient access to the binding posts when "connecting up " and permits ready inspection of the contacts. Fig. 73. Model 5 Form A Switch Cikcuit Controller Two circuits normal and two reverse, or four circuits normal, or four circuits reverse. The case is provided with main and supplementary covers as shown by Fig. 74, the latter protecting the contacts from frost and condensition at all times, and when the main cover is open, from rain. The trunking cap and operating crank may be applied to either side of the circuit controller as proves most convenient in installation. THREE POSITION D. C. MOTOR RELAY The Three Position D. C. Motor relay is especially designed for wireless control automatic block signaling, but is readily adapted for use with three position polarized line circuits. The operating mechanism consists of a small direct current motor ha\ing powerful permanent magnet fields with ample air gap between the armature and pole pieces. The contacts are moved from the de-energized position to either of the ELECTRIC INTERLOCKING HANDBOOK 99 Fig. '4. Model 5 Form A Switch Circuit Controller for Selecting Signal Circuits — Main and Supplementary Covers Open- Fig. 75. Model 5 Form A Switch Circuit Controller for Selecting Signal Circuits — Main Cover Open Two circuits normal and two reverse, or four circuits normal, or four circuits reverse. 100 GENERAL RAILWAY SIGNAL COMPANY energized positions by the rotary motion of the motor armature, the movement of which is transmitted to the contacts by suitable Hnk connections. The closing of one or the other sets of contacts is accomplished by a partial rotation of the armature, the direction being dependent on the polarity of the operating current. The contacts have the same opening and pressure, and are similar in design to^those used in the regular Model 9 D. C. relay. The maximum equipment of contacts in the four way relay, shown in Fig. 76, is four normal and four reverse, with four contacting fingers. It is to be noted that when used in connection with wireless signaling on polarized track work, the signal control is broken through one set of con- FiG. 76. Three Position D. C. Motor Relay Four way. tacts only, while in the polar-neutral relay the control miist be broken through both polar and neutral contacts. This same holds true for the track control, which, owing to the decreased resistance of the contacts introduced into the circuit, means that cut-sections can be employed to as great an extent in polarized track circuit work, through the use of this relay, as in the case of neutral track circuits employing the ordinary two position relay. The relay has several other important features which should be noted. The design is such that the chance of ha\dng the polarity reversed by a lai^ge flush of current or by lightning is so remote as to be negligible. The relay is not subject to residual magnetism troubles in any way, as its operation depends on current only, and not on electro-magnetic traction. This being the case, the drop away (50 per cent, of the normal pick up) cannot change with time, and once fixed, always ELECTRIC INTERLOCKING HANDBOOK 101 remains the same. The overall dimensions are such as to permit its installation in the space required By a D. C. tractive type relay having the same contacting capacity. TRACTIVE TYPE D. C. RELAYS Fig. Model 9 D. C. Shelf Relay Four way. Fig. 7S. Model 9 D. C. Wall Relay Four way. 102 GENERAL, RAILWAY SIGNAL COMPANY' ¥\ox K s ft a a < i i o 5 ir 1 li < 2 U u < < ft u ft u i ) 1 Hi 1 i X s '1 ^ ' 6 11 5 4 QU« 4 s z 2 B ** 5 5 S s I s 1 SS 3 •« ) ? S 3 S 5 8 5 1 -K '*iS >• 9 3 s^ n 9 s s: SB 8 S3 s s :q iS£ SJS 8S S KS»5fiSeS£SS^£»gS?^ 1 (2W? 59 5fi • o aoo le, give more than the amount of light required, an economy can be effected without sacrificing reliability by employii^ "cut in" relays which permit the burning of but one of the bulbs at a time. The coil ci this "cut in ' rday is connected in series with the bulb tha^ is to bum non the type and arrangement of the bulbs to be used in signal lamps, the next considoation should be with r^ard to the normal power supply and what reaerve should be provided to ke^ the lights burning in case of ecaer^eaacy- It IS recoipmoided as good practice that the signal lights should be <^>erated from a commercial source, the control being arranged so that the lighting systems will be quickly transferred on to the 110 volt interlocking battery in the event of failure of the commercial power. It will be seen that this use of tiie interiocking battery as a reserve restricts the lighting to <^>eration erated at any voltage desired. In such a case low voltage metallic fihument lamps can be operated, transmission about the plant being made at a higher voltage, thus avoiding the necessity of installing kige lifting mams. In this connection it is to be noted that low voltage li^Mmg should be restricted to points where the currrait supply is abso- ELECTRIC INTERLOCKING HANDBOOK 129 lutely reliable, except in the case of a plant with compara- tively few signals, at which plant a low voltage battery of suitable capacity is available for use as a reserve. In case commercial power, of the proper voltage, or sig- naling power cannot be secured, the lights should then be oper- ated from the charging generator, provision being made to transfer the lights onto the interlocking battery in case of failure of the generating unit. Attention is called to the undesirability of lighting from this source unless either the charging unit or interlocking battery is installed in duplicate, since if only one generator and one battery were employed, the capacity of the battery would have to be excessively large to provide sufficient reserve against the failure of the charging generator, such a failure in all probability being of longer duration than would be the case with commercial power. Precautions In operating the lighting system from a charging generator great care should be used to see that the normal voltage of the lamps is never exceeded, since the bulbs will be quickly burnt out if subjected to an excess voltage. This increased voltage always exists when the charging generator is supplying cur- rent for the lighting system at the same time it is charging the interlocking battery; therefore, a regulating device must be provided to maintain the voltage on the lamps at the normal point. This device ordinarily is a hand operated rheostat which has sufficient regulation to permit the voltage to be kept at normal. It will be seen that the device will require the maintainer's attention at frequent intervals; this, how- ever, cannot be considered serious, as under such conditions the interlocking battery would never be charged at night except in case of emergency. Where duplicate batteries are employed, a regulating device is not required, as the combination of switches on the power board can be so arranged that it is impossible to serve the lighting circuits from the battery that is being charged. Precaution respecting cross protection should be observed whenever the interlocking battery may be called upon to furnish current for the lighting system. At plants where the operating switchboard is equipped with the cross protection circuit breaker shown in Fig. 24 (both positive and negative battery connections being broken through the circuit breaker contacts) , the signals can be electrically lighted from the inter- locking battery without endangering the proper operation of the switches, signals, or other funcjtions of the plant. If, however, it is proposed to electrically light the signals of an existing G. R. S. plant at which plant the old type of circuit breaker (Sec. 1, Elec. Int. Cat., page 280) is installed, it is strongly recommended that the operating switchboard be equipped with the double pole circuit breaker (Fig. 24) and the circuits rearranged to embody the principles of the wiring 130 GENERAL RAILWAY SIGNAL COMPANY shown on ps^e 88, The lighting mains under no condition should be controUed through the circuit breaker. Recommendations It is recommended that two bulbs always be installed in each signal lamp, burning in multiple or operated in connec- tion with a "cut in" relay. Regarding the source of power, it is recommended as good practice tl^t commercial power be employed, providing arrangements are made to cut the lighting system onto the interlockii^ battery in case of failure of the commercial source. Where the interlocking plant is located in A. C. automatic signal territory the lighting may be operated on any voltage desired. At such a point high efficiency metallic filament lamps can readily be operated. No reserv^e is necessary, in view of the fact that tne signal transmission line is always thoroughly protected against power failure. Where neither commercial power nor A. C. signaling current is available, the signal lighting may be electrically operated from the charging generator, providing the interlocking bat- tery is (or batteries are) of sufficient capacity to insure the continuous operation of the interlocking and lighting systems through any period of time necessary to repair a failure on the part of the chai^ng unit. In all cases where storage batteries may be called upon to furnish current for the lighting circuits, regulating apparatus must be installed to permit the current from such battery to be delivered to the lighting mains at normal voltage during a chaining period. Wnenever the interlocking battery serves as a reserve, the circuits and apparatus on the operating switchboard must be such that operation of the lighting system will in no way endanger cross protection. SECTION V ELECTRIC LOCKING AND CHECK LOCKING GIVING A DESCRIPTION OF THE VARI- OUS TYPES OF CIRCUITS AND THEIR APPLICATION TO ELECTRIC INTER- LOCKING WORK ELECTRIC LOCKING ELECTRIC locking as defined by the Railway Signal ciation consists of "the combination of one or more elec- tric locks and controlling circuits by means of which levers in an interlocking machine, or switches or other devices operated in connection with signaling and interlocking, are secured against operation under certain conditions," Electric locking is a development of the tendency in rail- way signaling practice to constantly decrease the manual control of all functions and to increase the automatic control. The first important step along this line was the operation of switches and signals through the medium of interlocked levers concentrated in a central machine. The real beginning of electric locking, however, was in the installation at mechani- cal plants of locking circuits which were to prevent the lever- man from changing the route in the face of an approaching train. This was followed by a step which had its inception in the all-electric interlocking system : namely, section or detector locking which was designed to afford safety to a train from the time it passed the home signal location until it cleared the limits of the interlocking plant. As first installed in con- nection with electric interlocking, the switches and derails in a given track section were prevented from being thrown while a train was on that track section, by interrupting the current supply to those functions by means of a relay controlled by the track relay of the section in question. At the present time this method of control is not generally used with the all-electric system, having given way to the practice of equip- ping each switch and derail lever with electric locks, properly controlled by the various track sections. Ever since the time of those first successful installations, the signal men of the country have become more and more alive to the fact that safety of railway operation could be much further assured by the development of this principle of automatically preventing the operation of functions which might endanger the safety of trains approaching or passing through interlocking plants. In fact, at the present time electric locking has come to be considered by many a necessary adjunct to an interlocking plant. Due to the rapidity of the development of the art, a wide range of methods has been used to accomplish the same result; the principles involved, nevertheless, have been so nearly uniform that it has become possible to determine the elements that enter into good practice. For instance, it will be found that it should always be possible to restore the home signal to the normal position, even though it may not be desirable to release the route beyond. Also in case of emerg- ency, release of the route is generally permitted through the use of a time release or hand switch; the circuits are such that when the device has been operated to secure the desired 134 GENERAL RAILWAY SIGNAL COMPANY Fig. 96. Electric Time Release release, some circuit essential to the operation of either switch or signal functions will be broken, thus necessitating that the time release or hand switch be returned to its normal position before operation of the switches or signals affected can be resumed. Based on the above, the Railway Signal Association has classified Electric Locking in the following manner : "Section Locking. Electric locking effective while a train occupies a given section of a route and adapted to prevent manipulation of levers that would endanger the train while it is within that section." An illustration of section locking is given in Fig. 97, showing the manner of controlling the locks with which the switch levers are equipped. As the levers are locked in either the full normal or full reverse position, it will be seen that the z^ ,^"^ roll normal and II QIO reverse locks ■^ ^ "^ on switch levers Fig. 97. Section Locking Circuit ELECTRIC INTERLOCKING HANDBOOK 135 operator is prevented from changing the position of the switches or derails in a given section during such time as that section is occupied or fouled by a train. " Route Locking. Electric locking taking efifect when a train passes a signal and adapted to prevent manipulation of levers that would endanger the train while it is within the limits of the route entered." Route locking is a development of section locking in which the switches and derails in all sections of any route are locked Pepeatin^ relay for Section UT (See note) T_ir 1 K^tnoi^j^ — , ( 5€c note ) Full normal and ^, i t f . |f(--T, ,f reverse lock on — ^H I ^ " U U snitch lever 14 JC-C Repeating XjT- — relay for -^ C Section \l T ' Full normal and reverse lock on srfitch lever \ Z Fig. 98. Route Locking Circtjit Note. — To positive battery through lever contacts and relays as de- termined by the layout of track indicated by dotted lines.. from the time a train enters that route until such time as the route is cleared. An illustration of route locking applied to a simple layout is shown in Fig. 98. It is evident that the circuits become somewhat complicated when used in connec- tion with an interlocking where the routing of each signal may extend over a number of combinations of track sections. "Sectional Route Locking. Route locking so arranged that a train, in clearing each section of the route, releases the locking affecting that section." ' This is a further development of section locking in which the functions in all sections in a given route are locked as 136 GENERAL RAILWAY SIGNAL COMPANY soon as the train has passed the home signal, the functions in each section, however, being released behind the train as soon as the train has passed out of the section. The installation of sectional route locking has been largely restricted to points such as congested terminals where the maximum number of traffic movements is demanded uath a maximum of protection. Due to its being little used, and on account of the rather complicated circuits involved, no at- tempt has been made to show any typical illustration of the circuits required in such work. AnnuncU+or + Control Screw Release Half reyerse lock on 5i9ndl lever 6 Fig. 99. Approach Locking Circuit "Approach Locking. Electric locking effective while a train is approaching a signal that has been set for it to proceed and adapted to prevent manipulation of levers or devices that woiild endanger that train." Fig. 99 shows an approach locking circuit in which a half reverse lock on the home signal lever, through the medium of the locking between the signal and switch levers, prevents the release of the route during such time as the lock is de-energized. The locking becomes effective after the signal for the route has been cleared and the train has passed a predetermined point, which in Fig. 99 is the annunciator section; the locking is released as soon as the train passes the homje signal. It will be noted that in Fig. 99 no protection is given after the train has passed the home signal, i. e. — no route locking protection is afforded. Protection can be given through the plant by releasing the signal lever in the firet section beyond the limits of the plant instead of on the forty-five degree control relay. ELECTRIC INTERLOCKING HANDBOOK 137 "Stick Locking. Electric locking taking efifect upon the setting of a signal for a train to proceed, released by a passing train, and adapted to prevent manipulation of levers that would endanger an approaching train." Stick locking in reality is only another form of approach locking, being different in that it becomes effectve on the reversal of the home signal lever and does not further depend on the approach of a train. Fig. 100 shows a stick locking circuit in which the half reverse lock, with which the signal lever is equipped, prevents its return to the full normal position, and, therefore, the release of the route governed, until such time as a train has passed on to the release section ; this section is shown located beyond the interlocking limits as mentioned under "Approach Locking." n : 5creyi Release^, ? lu "t 'I TT Half reverse lock Con+rol 5i9 6-»-h__ i;:^ on Signal lever 6 Fig. 100, Stick Locking Cikcdit It will be seen that it is necessary to restore the signal lever to the normal position while the train is on the releasing section, otherwise the signal lever can only be returned to the full normal position through the operation of the time release. If desired, the releasing section may be extended to include the several track sections in the route so that the lever may be restored to the normal position any time the train is within the limits of the route. "Indication Locking. Electric locking adapted to prevent any manipulation of levers that would bring about an unsafe condition in case a signal, switch, or other operated device fails to make a movement corresponding with that of the operating lever ; or adapted directly to prevent the operation of one de- vice in case another device, to be operated first, fails to make the required movement." As an illustration of this type of locking may be taken any electrical device, which is designed to indicate the cor- respondence of position between a unit and its controlling 138 GENERAL RAILWAY SIGNAL COMPANY lever. The simplest example is the indication of the position of a semaphore blade by means of a lock or other device on the governing lever, the control of this lock being carried through the circuit breaker on the signal. The well-kno\^Ti dynamic indication of the aU-electric system is a striking example of indication locking. It will be found that with the exception of certain forms of indication locking, such as the d>Tiamic indication, the differ- ent l^sic forms of electric locking as outlined above are seldom used alone, but in combinations. 9HcK Relay ^^*pi\ nfi iiio ^ "^ Full Normal and Reverse locKs on Switch Levers. Fig. 101. CiKCurts for Combixatiox of Approach, Indicatiox AMD Section Lockdcg Fig. 101 illustrates the use of an approach locking circuit in conjunction with section locking; and with indication locking for distant signal No. 1. In this circuit the control is secured by equipping the switch levers with electric locks governed by a stick rday. The locking becomes effective when signal No. 6 is cleared but is capable of being released by the return of lever No. 6 to the normal position, providing a train has passed into the releasing section, or providing no train is on any of the track sections repeated by the annunciator and the forty-five degree control relay for signal No. 6. This circuit does not require that the lever be returned to the normal position whUe the train is on the releasing section. ELECTRIC INTERLOCKING HANDBOOK 139 If this feature is desired the control may be broken through the contacts on lever No. 6 instead of through the circuit breaker of the signal. The indication locking feature consists of carrying the control of the stick relay through the circuit breaker of dis- - tant signal No. 1 to prevent release of the route under any condition if signal No. 1 is not in the caution or stop position. Fig. 102 illustrates* a similar arrangement of tracks and sig- nals, with circuits providing stick locking, section locking, and indication locking. It is to be noted that in every particular Stick Relay Full Normal -and Revcr^se lockft on Switch Levers Fig. 102. Circuit for Combination of Stick, Indication and Section Locking this circuit is the same as that in Fig. 101, except that the stick relay does not have a pick up through the forty-five degree control relay and the annunciator in series; the omission of this wire classes the circuit under "Stick Locking." The locking becomes effective upon the clearing of signal No. 6 and is released hy a train on the clearing section or by operation of the time release. CHECK LOCKING WHEN interlocking plants are located a comparatively short distance apart, it is advisable and frequently necessary to install what is known as "Check Lock- ing," which enforces cooperation between the levermen at the two plants in such a manner as to prevent opposing signals, governing over the same track, from being at proceed at the same time. Furthermore, after a signal has been cleared and accepted by a train, -check locking prevents an opposing signal at the adjacent interlocking plant from being cleared until the train has passed through to that plant. Fig. 103 shows a check locking circuit which involves the use of check lock levers at each plant, the arrangement and method of operation of these levers making the circuit especially z F=^ n^o . "U BlA -LATCH CCMnCT n^p^ ^^^iL Fig. 103. Check Locking Circuit For use where there is no preference as to direction of traffic. adaptable where there is no preference as to the direction of traffic. The signal levers at each station, governing move- ments over the intervening track, are so interlocked with the check lock levers in their respective machines, that they may not be moved from their full normal position until their re- spective check lock levers have been moved to the full reverse position. By reference to Fig. 103 it will be seen that the check lock levers are so controlled that but one of them can be in the full reverse position at the same time. Therefore, it is impossible for signals No. 1 and No. 20 at stations A and Z, respectively, to be displayed at proceed at the same time. The control circuit for the check lock levers is shown broken through relay X, which represents the track relays for the sections between signals No. 1 and No. 20. This prevents a check lock lever being thrown to the full reverse position and, consequently, any traffic movement from being made during such time as these sections are occupied. The release ELECTRIC INTERLOCKING HANDBOOK 141 of either lever in moving to the reverse position is effected by current taken from the battery at the far end of the circuit. The check locking circuit shown in Fig. 104 is designed for operation when there is a preference in the direction of traffic, since traffic movements can normally be made from A to Z without any interference from the check locking, it being necessary, however, when making a movement from Z to A (against traffic) to operate both check lock levers. Each station is equipped with a check lock lever so interlocked with signal levers No. 1 and No. 20, that lever No. 1 is free to be moved only when the check lock lever at A is full normal, and lever No. 20 only when the check lock lever at Z is full reverse. The control, however, of the check lock levers is such that the lever at Z can be reversed only ^ £0 £L a-^^ Fig. 104. Check Locking Circuit For use where there is preference as to direction of traffic. after the check lock lever at A has been thrown to the full reverse position, and, after having been moved from its normal position, the lever at A can be returned to the full normal Rosition only after the return of the check lock lever at Z to ill normal. Thus it will be seen that it is impossible to have a condition existing which would permit signal levers No. 1 and No. 20 to be reversed at the same time. The final movement of the check lock lever at Z in being moved to the full reverse position, and of the check lock lever at A in being placed normal, is permitted by energy secured from the battery located at the far end of the circuit. SECTION VI INSTALLATION AND OPERATING DATA FOR POWER PLANTS AND SWITCHBOARDS COVERING LEAD TYPE STORAGE BAT- TERIES, GENERATORS AND MOTOR GENERATORS, GASOLINE ENGINES AND SWITCHBOARDS, WITH DATA AND TABLES FOR THE DETERMINATION OF THE PROPER TYPE AND CAPACITIES OF APPARATUS LEAD TYPE STORAGE BATTERIES STORAGE or secondary; batteries consist of cells, the plates and electrolyte of which can be restored to their original condition after discharge, by forcing an electric current through the cell in the direction opposite to that taken by the current produced by the cell. When a primary battery is exhausted the electrolyte and elements are renewed before further use. It is in this reversability or regeneration that lies the fundamental difference between storage and primary cells. The lead type storage cell consists essentially of two plates or sets of plates suspended in a dilute solution of sul- phuric acid. There are many forms of plate construction, but the chemical composition is generally the same, the positive and negative plates being made of peroxide of lead and pure •■ -I Rr rn FrH ftt^ ^ !'\ < f^^* <=J»=i fJ j f^ f gmcijnnn o o i § H Fig. 105 Lead Type Storage Battery and Battery Rack or "sponge" lead, respectively. When the elements are com- posed of more than two plates the negative plates in each cell are one more in number than the positives. Wooden or hard rubber separators are introduced between the plates to prevent any of the positives from coming into contact with the negative plates, thus causing short circuit. When the circuit is closed and the battery discharging, the sulphuric acid combines with the lead in the elements forming a deposit of sulphate of lead on the surface of both positive and negative plates, the density (specific gravity) of the electrolyte diminishing as the sulphuric acid leaves it to com- bine with the materials of the plates. By forcing current through the cell in the direction opposite to that of the dis- charged current, the sulphate of lead on the negative plates will be converted into sponge lead and sulphuric acid, and the sulphate of lead in the positive plates into peroxide of lead and sulphuric acid ; the sponge lead and the peroxide of lead remain in the plates and the sulphuric acid diffuses in the electrolyte, the specific gravity of which rises in consequence. 146 GENERAL RAILWAY SIGNAL COMPANY Approx. Weight of Electrolyte i4 10.75 18.75 22.00 27.25 55.00 59.75 Approx. Weight of Cell Comp. 3 37.56 63.65 80.25 112.16 189.86 217.61 Approx. Installa- tion Height 1 I w 1 COOOOOO^ i o 1 c © ® - 00 Cl (N ooo»cio i A s OiOOO^^ O 1 a 1 < 1 gffllf Number of Plates per Cell »CHOt^ — C5-H Normal Charging Current at 8-Hour Rate 1 "'SSS^g 6 ffl d S < §§gll§ ELECTRIC INTERLOCKING HANDBOOK 147 EXTRACT FROM R. S. A. SPECIFICATIONS FOR LEAD TYPE STATIONARY STORAGE BAT- TERY FOR INTERLOCKINGS (1913) 1. Intent The intent of these specifications is to provide for the furnishing of complete storage battery cells and parts, designed to be located in interlocking stations or battery- houses and used for operating interlocking and signal apparatus. 2. Designations (a) In ordering cells or parts the nominal capacity re- quired will be designated as "40 A. H., "80 A. H.," "120 A. H.," "200 A. H.," "320 A. H.," or "400 A. H.," and these terms shall be understood to signify, on an eight (8) hour basis, the capacities and dimensions thus designated in these specifications and Bailway Signal Association drawing 1224. (See page 146.) (6) Each complete cell, unless otherwise specified,^ is understood to include the following parts : 1. One (1) positive group, consisting of the neces- sary number of positive plates assembled with con- necting strap and one (1) connecting bolt. 2. One (1) negative group, consisting of the neces- sary number of negative plates assembled with con- necting strap and one (1) connecting bolt. 3. One (1) set of separators, with dowels and hold downs. 4. One (1) glass jar. 5. One (1) glass sand tray, with moulded feet. 6. One (1) glass cell cover. 7. Required electrolyte. (c) Positive or negative groups, if ordered separately, will be ready for service after an initial chaise continued for fifty (50) to sixty (60) hours at the eight (8) hour rate. 3. Capacity of Battery In conformity with service requirements. 4. Number of Cells per Battery In conformity with voltage requirements. 5. Dimensions Jars, sand trays and covers must conform to Railway Signal Association drawing 1224, which is an essential part of these specifications. (See page 146.) 6. Elements (a) Positive plates shall be of the Plante type. 148 GENERAL RAILWAY SIGNAL COMPAVi' (h) Negative plates shall be either of the Plante t>T)e or of the type having mechanically applied active material. (c) Positive and negative plates shall be respectively connected into positive and negative groups by burning to lead straps. 7. Separators Separators shall' be of sj>ecially treated wood. 8. Electrolyte (o) Electrolyte shall have a specific gravity of between 1.205 and 1.215 at the end of the initial charge in service. (6) Electrolyte shall be in accordance with RaOway Signal Association specifications. 9. Acceptance No unit or part will be accepted which does not, in the judgment of the Purchaser, conform to the best practice with respect to material and workmanship. 10. Service Requirements (a) It is essential that all parts shall be rujgged in the highest degree both mechanically and electrically. The apparatus furnished must give satisfectory and economical service. (6) Should any injurious buckling of plates occur in normal service withm one (1) year after delivery, or should the capacity of any cell or element fall to less than aghty-five (85) per cent, of the specified capacity at the eight (8) A. H. rate, in normal service, within one (1) year after delivery, the Contractor must replace the drfective parts and restore the affected cells to their full specified capacity and to a condition satisfactory to the Purchaser, without additional cost to him. (c) As far as practicable, it is understood that the cells are to be operated in the mann^ reconmiended by the Contractor, but the necessities of operation must be the first consideration. R. S. A. DIRECTIONS FOR INSTALLATION OF LEAD TYPE STATIONARY STORAGE BATTERIES (1909) General (a) The battay should be housed in a space by itself as the acid fumes given off during the charge are of a cor- rosive nature. This space should be well ventilated, well lighted, and as dry as possdble. If the space is speci- ally constructed it should contain no metal work other than lead. If this is not possible, th^i such metal parts ELECTRIC INTERLOCKING HANDBOOK 149 should be protected by at least two (2) coats of acid-proof paint. The floors of a large battery room should be preferably of vitrified brick, jointed with pitch. (6) Batteries should be placed in a room having a uni- form temperature, preferably seventy (70) degrees Fahr. Low temperature does not injure a battery, but lowers its capacity approximately one-half (Vs) of one per cent, per degree. Excessively high temperatures shorten the life of the plates. (c) If glass jars are used and cell is not of the two-plate type, the following should be observed : 1. Batteries up to four hundred (400) ampere hour capacity shall be placed in glass jars. 2. The capacity of batteries shall be for an eight (8) hour rate of discharge at seventy (70) degrees Fahr. 3. Batteries having a large number of cells, such as at interlocking plants, shall be provided with sub- stantial wood racks to support them. These racks shall preferably be made of long-leaf yellow pine with non- corrosive fastenings, and thoroughly protected by at least two (2) coats of acid-proof paint. Cells shall be arranged transversely, and the layouts be such that each cell is accessible for inspection and provide suf- ficient head room over each cell to remove the element without moving the jar. 4. Each jar shall be set in a tray which has been evenly filled with fine dry bar sand, the trays resting on suitable insulators. 5. When placing the positive and negative groups into the jars see that the direction of the lug is rela- tively the same in each case, so that a positive lug of one (1) cell adjoins and is connected to a negative lug of the next cell throughout the battery, thereby giving proper polarity, providing a positive lug at one free end and a negative at the other. 6. Before bolting the battery lugs together, they should be well scraped at the point of contact, to insure good conductivity and low resistance in the circuit. The connector studs should be covered with vaseline before screwing up, and all connections covered with vaseline or suitable paint. 7. Before putting electrolyte in the battery the cir- cuits connecting same with the charging source must be completed, care being taken to have the positive pole of the charging source connected with the positive end of the battery and the negative poles. The electrolyte should cover the top of plates by one-half (V2) inch. Electrolyte (a) The electrolyte must be free from impurities and meet the tests prescribed by the Railway Signal Association. 150 GENERAL RAILWAY SIGNAL COMPANY 3. Initial Charge (o) The initial charge must follow the Manufacturer's instructions. The charge should be started promptly as soon as all the cells are filled with electrolyte, and all con- nections made, usually at the normal rate, and continued at the same rate untO both the specific gravity and voltage show no rise over a period of ten (10) hours, and gas is being freely given off from all the plates. The positive plates will sometimes gas before the negatives. Gen- erally, to meet these conditions, from forty-five (45) to fifty-five (55) hours continuous charging at the normal rate will be required; and if the rate is less, the time required will be proportionately increased. In case the charge is interrupted, particularly during its earlier stages, or if it is not started as soon as the electrolyte is in the cells, the total chaise required (in ampere hours) vn.\\ be greater than if the charge is continued and is started at once. (b) As a guide in foUo^^ing the progress of the charge, readings should be regularlv taken and recorded. The gassing should also be watched, and if any cells are not gassing as much as the adjoining ceUs, they should be carefully examined and the cause of the trouble removed. The temperature of the electrolyte should be closely watched, and if it approaches one himdred (100) degrees Fahr. the charging rate must be reduced or the charge temporarily stopp^ until the temperature lowers. (c) The specific gravity will fall after the electrolj^ is added to tne cells, and will then graduaUv rise as the charge progresses, imtil it is up to 1.210 or thereabout. (d) The volts^e of each cell at the end of the charge will have risen to its maximimi and usually will be be- tween two and five-tenths (2.5) and two and seven-tenths (2.7) volts. («) If the specific gravity of any of the cells at the com- pletion of the charge is below 1.205, or above 1.215, allow- ance being made for the temperature correction, it should be adjusted to within these limits, by removing and adding electrolyte if the specific gravity is low, and adding chemi- cally pure water if the specific gravity is high, to again bring the surface at the proper height above the top of the plates. It is of the utmost importance that the initial charge be complete in every respect. (/) In case of batteries charging from primary cells, if possible, the initial charge should be given at a place where direct current is available of sufficient voltage to complete the charge at the normal rate, the cells being then transferred to their permanent position. 4. Tw(«»LATE Cells The general method of installation is the same as the above with the following exceptions: Each cell contains ELECTRIC INTERLOCKING HANDBOOK 151 one positive and one negative plate, the positive of one cell being solidly connected by a lead strap to the nega- tive plate of the adjoining cell, and consequently no con- nectors are required. At the ends of each row there is one (1) free positive plate and one (1) free negative plate respectively, which constitute the positive and negative terminals of that row. Connections to these terminal^ are made with bolt connectors. Large Capacity Cells (a) Batteries of a greater capacity than four hundred (400) ampere hours shall be placed in wood tanks and shall be covered by special specifications. (6) Where tanks are used, it is customary to support them on a double tier of glass insulators. (c) Plates are shipped separately and assembled one at a time in the tank and burned solidly to a heavy lead bus bar by means of a hydrogen flame. It is recommended that when installations of this kind are required that battery Manufacturers install the battery in accordance with their standard practice. R. S. A. INSTRUCTIONS FOR OPERATION OF LEAD TYPE STORAGE BATTERIES AT INTER- LOCKING PLANTS (1909) 1. Battery batteries ; cells each ; type ; munber of plates per cell normal charging rate amperes. batteries ; cells each ; type ; number of plates per cell normal charging rate amperes. 2. Pilot Cell In each battery, select a readily accessible cell, to be used in following the daily operation of the battery, by taking specific gravity readings of the electrolyte, as given below. Keep the level of the electrolyte of this cell at a fixed height, one-half {V2) inch above the top of the plates, by adding a small quantity of chemically pure water each day; this is extremely important. 3. Charging (o) When to charge. 1. As a general rule, do not chaise until the specific gravity of the pilot cell has fallen at least ten (10) points below the preceding overcharge maximum, the battery being then about one-third (Vs) discharged. 2. In any case, charge as soon as possible after reach- ing either of the limits given below under "Discharging," or if for any reason a heavy discharge is expected. 152 General railway signal company (6) Regular charge. 1. Charge at normal rate of amperes, or as near as possible, and continue until the specific gravity of the pilot cell has risen to three (3) points below the maxi- mvan reached on the preceding overcharge, when the charge should be stopped: for example, if the maxi- . mum specific gravity on the overcharge is 1.207, the spe- cific gravity reached on regular charge should be 1.204. 2. The cells should all be gassing moderately. (c) Overcharge. 1. Once every two (2) weeks, on -"" prolong the regular chaise until fifteen (15) minute read- ings of the specific gravity of the pilot cell and of the battery voltage, taken from the time the cells commence to gas show no rise on five (5) successive readings, thus having been at a maximum for one hour. 2. When the above method of overcharge is not prac- ticable, the overcharge may be given every sixth charge, provided the battery receives an ovCTcharge at least once every month. If in following this method, i. e., where the overcharge is given at intervals longer than two (2) weeks and not less frequently than once a month, tiie regular charge should be prolonged until one-half (¥2) hour readings of the specific gravity of the pilot cell and of the battery voltage, taken from the time the cells begin to ^s, show no rise on seven (7) successive readings, thus having been at the maximum for three (3) hours. 3. The cells should all be gassing freely. 4. The overcharge should be given whether the bat- tery has been in regular use or not. (d) Charging in series. If two (2) or more batteries are charged together, in series, care should be taken that each battery is cut out when fully chained ; in other words, if one of the batteries discharges less than the other it should not receive the same chaise. 4. Discharging (a) Never allow the specific gravity of the pilot cell to fall more than about thirty (30) points below the preceding overcharge maximum. As a rule, do not allow specific gravity to fall more than twenty (20) points. (b) Never allow the volt^e to go below one and EIGHTY-FIVE ONB-HUNDREDTH3 (1.85) VOLTS PER CELL when discharging at the normal rate ( amperes). If the rate of d^harge is less than the normal rate, the voltage should not be allowed to go so low. Limiting voltage cells volts. Limiting voltage cdls volts. (c) Never allow the battery to stand in a completely discharged condition. electric interlocking handbook 153 5. Readings (a) Read and record the specific gravity of the pilot cell and battery voltage just before starting and ending every charge, together with the temperature of the electrolyte. (b) To properly compare the specific gravity readings, they should be corrected to standard temperature (seventy (70) degrees Fahr.) by adding one (1) point for every three (3) degrees above, and subtracting one (1) point for every three (3) degrees below standard temperature. (c) Once every two (2) weeks, after the end of the charge preceding the overcharge, read and record the gravity of each cell in the battery. 6. Inspection (a) Carefully inspect each cell on the day before the overcharge, using a lamp on an extension cord for the purpose. Examine between the plates and hanging lugs to make sure that they are not touching, and also make a careful note of any peculiarity in color, etc., of the plates. (6) Use a strip of wood or hard rubber in removing short circuits. Never use metal. (c) Toward end of the charge preceding the overcharge, note any irregularity of gassing; cells gassing slowly should be investigated. 7. Indications of Trouble (a) Falling off in specific gravity or voltage relative to the rest of the cells. (b) Lack of or slower gassing on overcharge, as compared with adjoining cells. (c) Color of plates markedly lighter or darker than in adjoining cells, except that sides of plates facing glass may vary considerably. (d) In case of any of the above symptoms being found, examine carefully for cause, and remove at once. (e) Report trouble of any description at once to Broken Jars If a jar should break, and there is no other to take its place, so that the plates will have to remain out of serv- ice for some time, keep the negatives covered with water and allow the positives to dry. Connect into circuit again just before a charge, so that the plates will receive the benefit of the charge. Other Important Points (a) Plates must always be kept covered with electro- lyte. (b) Use only chemically pure water, preferably dis- tilled, to replace evaporation. 154 GENERAL RAILWAY SIGNAL COMPANY (c) Never add electrolyte except under the condi- tions explained above. (d) Never allow the sediment to get to the bottom of the plates; remove sediment when the clearance has I cached one-half {¥2) inch. (e) Ventilate the room freely, especially when charging. (/) Never bring an exposed flame near the battery when charging. (jg) Never allow metals or impurities of any kind to get into the cells; if this happens, remove ancTwash the plates and renew the electrolyte. (fc) Fill out the report dieets regularly. (t) Read the general instructions carefully. REQUIRED CAPACITY OF STORAGE BATTERIES USED WITH G. R. S. ELECTRIC INTERLOCKING A storage battery of fifty-five to fifty-seven cells, having an approximate potential of 110 volts, is used in connection with G. R. S. electric interlocking installations. The required ampere hour capacity is dependent on a number of variables, viz: the nimiber of days between charges, frequency of lever movfflnents, amount of current required for lighting, for cut- outs, indicators, annunciators, etc., and the numba* of days of reserve power desired. A separate low voltage battery is generally installed when there are a number of locks, indicators, relays, etc., required at the plant, as this type of device is more efficient and can have a more rugged magnet winding when designed for opera- tion on a potential of 10 or 20 volts; furthermore, there are certain safety features which can be secured in connection with this low voltage control. The capacity of such a low voltage battery is determined in the same manner as the high voltage battery, as given hereaft^". The following instructions will enable the determination, with reasonable accuracy, of the ampere hour capacity of the battery required for use with a G. R. S. electric interlocking plant. Ampere Hour Capacity Required for Operation of Functions (See also table on page 158.) The ampere hour capacity required for the operation of functions is obtained by multiplying the number of lever movements per day by the nimtb^* of days between charges and by a "Function Constant." This constant, to be obtained by reference to table on page 155, is influenced mainly by two things: the avenge length of time that signals are held in ELECTRIC INTERLOCKING HANDBOOK 155 the proceed position and the ratio of the number of signal movements to switch movements. In the absence of definite information on these points it is suggested that the constant .006 be used as representing a fair average condition. This constant is shown underlined in the table. By reference to the table of Function Constants it can be easily seen that it is advisable to keep down the length of time signals are held in the proceed position, a glance indicat- ing that the battery capacity will run up very rapidly as the time of holding signals at proceed increases. In this connec- tion it may be stated that there have been cases where a much smaller size battery has been permitted due to the saving in TABLE OF FUNCTION CONSTANTS Average Length of Time Signals are Held in Proceed Position Minutes Ratio of Signal to Switch Movements j 1-2 1-3 1-4 1-5 2 3 5 10 15 30 .006 .007 .010 .016 .022 .041 .005 .006 .008 .013 .017 .032 .005 .006 .007 .011 .015 .026 .005 .006 .007 .010 .013 .023 hold clear current, this being effected by the installation of annunciators, which by suitably indicating the approach of a train reduces the length of time of holding the signals at proceed. Furthermore, it is interesting to note that the saving effected by the installation of this smaller battery may more than balance the cost of such annunciator installation. Ampere Hours Required for Operating Switchboard Cut-Outs In every G. R. S. electric interlocking plant one or more circuit breaker cut-outs are required for cross protection pur- poses. The capacity required for cut-outs is obtained by multiplying the number of cut-outs by nine-tenths and by the number of days between charges. A discussion as to the number of cut-outs to be employed to suitably sectionalize a plant is given on page 93. Ampere Hours Required for Electric Lighting (See page 127.) When the signals at an interlocking plant are to be lighted by electricity, the interlocking battery is generally held as a reserve against the failure of the normal source of power. The number of days which the battery may be called upon to 156 GENERAL RAILWAY SIGNAL COMPANY furnish current in such an event depends upon the probable length of time required to repair any derangement of the apparatus normally furnishing power to the lighting system. The ampere hour capacity which must be provided for the lighting is, therefore, determined by multiplying the ampere hours per signal per day by the number of signals to be lighted and the number of days' operation which may be required between charging periods. TABLE OF AMPERE HOURS PER DAY PER SIGNAL. 110 VOLT CARBON FILAMENT BULBS — TWO BULBS PER SIGNAL, CONNECTED IN MULTIPLE Candle Power per Bulb Average Number of Hours Lights are Burxed PER Day 12 13 j . 14 Ampere Hours Ampere Hours | Ampere Hours 2 4 2.18 4.36 2.36 2.55 4.72 5.09 Note. — Values approximate. Ampere Hours Required for Miscellaneous Purposes When auxiliary devices, such as indicators, locks, etc., are operated from the interlocking battery, the current taken for this purpose must be included in figuring the capacity of the battery. The current required by these devices can be secured by reference to tables on pages 265 to 269. The capacity of battery required for this purpose is obtained by multiplying the current taken by said auxiliary devices by the average number of hours such apparatus is energized per day, and by the num- ber of days between charges. Reserve Ampere Hours Under normal operating conditions the battery should not be fully discharged on account of the fact that charging cur- rent may not be always instantly available when wanted, in which case the time would surely come when the plant would be without means of operation. It is, therefore, necessary to have the battery of such size that at the usual time of charging there will be a certain number of ampere hours capacity left in the battery as a reserve. The R. S. A. recommends that under normal conditions the battery never be discharged beyond two-thirds of its total capacity; stated in other words, this means that 50 per cent, must be added to the capacity computed when installing the batteiy in accordance with R. S. A. specifications. If the ELECTRIC INTERLOCKING HANDBOOK 157 battery is to be charged at intervals of a week this will give a reserve of three and one-half days, and if at intervals of two weeks the reserve will be for seven days. When a com- mercial source of power is available, this in all probability will give more reserve than would be necessary. On the other hand, if the charging source is not so reliable, the capacity of the battery may Imve to be increased. For instance, the charging of the batteries at an isolated plant may be dependent upon a gasoline engine, the failure of which might take several days for repairs due to time spent in securing repair parts, etc. In such a case when the charging is done at intervals of a week, it would, perhaps, be necessary to have a reserve suf- ficient for a full week's operation, this requiring that the computed capacity of the battery be increased by 100 per cent. Based on the above, it is recommended as good practice that the battery provide for a minimum reserve of 50 per cent, and that, if local conditions require it, an additional amount of reserve be added as outlined above. Method of Tabulation When determining the capacity of a batterer the different items may be tabulated as shown below; in which— L stands for "lever movements per day." C stands for "function constant." D stands for "days operated between charges." N stands for "number of units operated." - AH stands for "ampere hours per day per signal." A stands for "amperes." H stands for "hours energized per day." Functions LxCxD = ampere hours Cut-Outs %o X H X D = ampere hours Lighting Signals •. . .AH x N x D = ampere hours Auxiliary Apparatus . . . . A x H x N x D = a mpere hours Total of above = .ampere hours Reserve to be added = .a mpere hours Total capacity of Battery = ampere hours When the Number of Lever Movements is Not Known When it is not possible to ascertain the number of lever movements to be made in a given plant, the ampere hour capacity of battery required for the operation of functions and for cut-outs can be secured from the following table; these figures include sufficient reserve to care for ordinary conditions. 158 GENERAL RAILWAY SIGNAL COMPANY TABLE GIVING BATTERY CAPACITY FOR OPERATION OF FUNCTIONS AND CUT-OUTS Size of Machine Size of Battery 8 to 16 levers 16 to 32 levers 32 to , 48 levers 48 to 88 levers 88 to 128 levers 128 to 168 levers 40 ampere hour battery 60 ampere hour battery 80 ampere hour battery 120 ampere hour battery 160 ampere hour battery 200 ampere hour battery The table is based on past experience and is considered rea- sonably correct for moderate size machines, the battery sizes, if anything, being somewhat high. The table is not extended for machines larger than 168 levers, as with such plants it. is believed that special study of lever movements should be made in the determination of the battery size. If the signals are to be lighted and auxiliary apparatus operated from the interlocking battery, an additional number of ampere hours must be added to the figures in the table, the calculation being made in accordance with the preceding paragraphs dealing with the capacity required for electric lighting and for miscellaneous purposes. iim iMnrr r^m rRONT ELtVATION SOTIOri A B. Fig. 107.' Lead Type Storage Battery and Battery Cupboard ELECTRIC INTERLOCKING HANDBOOK 159 1. cury ectlfli Input ^ 8 § 8 8 8 8 8 8 8 8 « ^ ^ (N CO ■<*< «o • >. 2 i < 5 s § a- 8 8 § s g 8 CJ N C4 CO rj< •< fl O 0.0 • -> o o) 5 " '^^.ain aj 2: S H 73 00!' 2 c* .2^0 |< I 2.20 u_§-c^ c « " "^ " "" -I 11^^ I • .3 *^ O o o I W S S c S-i:-S 5|3 ^> •2 § S S S S ^J^ c « a3 S';3 bs'J S § t- c fl-S£^® 8^33 Hi i •^ o S S C! § "^ (3 o o o «J^ i: hT3 J:; t-^ C 3 O 160 GENERAL RAILWAY SIGNAL CX)MPAN^' G. R. S. BATTERY CHARGING SWITCH The battery charging switch illustrated by Fig. 108 provides a simple and efl&cient means for connecting storage batteries in series with charging and dischai^e lines, permitting the batteries to be switched off or on to the line without opening the chajging circuit. During the manipulation of the switch, short circuiting of the battery is avoided by automatically inserting a resistance during the interval that the battery would othen^-ise be on Fig. 108. Battery Chabging Switch short circuit, which resistance is again cut out as soon as that point is passed. Manipulation of the switch is simple, the four different positions of the switch controUing the battery as follows: 1 — Battery A dischai^ing, Battery B charging. 2 — Battery A discharging, Battery B open. 3 — Battery B discharging, Battery A open. 4 — Battery B discharging, Battery A charging. The charging switch is compact and substantial in design and so arranged to permit of easy inspection. The commu- tator possesses a mgh degree of insulation. The contact Elates and fingers are lai^e, being designed to take care of the eavy currents necessary in this kind of work without heating. ELECTRIC INTERLOCKING HANDBOOK 161 .2^ Go "cS OS be » a a, •a o u -fl a z PO w ^ «e 2ffi .2 a pq« ° s K O -< ^ Q 'mm ^ c 03-- OS pfl ^ O .^^ . DIRECT CURRENT GENERATORS General Description of Charging Apparatus DIRECT current generators of the shunt wound type are ordinarily used for storage battery charging. The capacities of the generators used in connection with the G. R. S. electric interlocking system run from 1 to 8 K. W., as shown in the table on page 159, the current being delivered at a potential ranging from 110 to 160 volts. Where commercial power is available, it is preferable to use a direct connected motor for operating the charging gen- erator. Where such power is not available, a gasoline engine is generally employed to drive the generator, either by means of belting or by being directly connected to the generator. The charging is generally controlled through the medium of a power switchboard equipped with a no-load, reverse-current circuit breaker, which opens the charging circuit if the gener- ator voltage drops below that of the batteries, thus preventing the generator from running as a motor on current delivered by the batteries. A simplified charging circuit is shown by Fig. 110. In this circuit the generator is assumed connected for right-hand rotation; to secure left-hand rotation the field connection should be reversed. Setting up the Machine The generator should be located in a room which is as dry and clean as possible: a room which is hot and dusty should be avoided, particularly if the dirt is of a gritty character, as it is apt to injure the commutator and bearings of the machine. The machine should be in plain sight and have sufficient room on all sides for easy access, care being taken that there is sufficient room to permit taking out the armature. If the flooring of the power house is firm, the generator or motor generator set may be mounted on a wood block three or four inches thick, screwed to the flooring ; if the floor con- struction will not permit this, a concrete foundation should be installed. When Starting Generator for the First Time Before starting the machine for the first time, make sure that the main switch and circuit breaker are open (Fig. 110). Raise the brushes from contact with the commutator and^ examine them to see if they are in proper condition. Fill the bearings with oil. Make sure that the armature and field coils of the generator have not become wet during shipment or while being stored ; if any sign of dampness is noted they should be dried out, following the instructions on page 165. Run the generator light for a time, noting whether the oil rings are working properly, and if the generator is belt driven, ELECTRIC INTERLOCKING HANDBOOK 163 note whether the machine is so Uned up that the belt runs central on the pulleys and the armature plays freely back and forth between its bearings. At no-load the speed of the gener- tor should be slightly high, so that at full-load it will come down to approximately that indicated on the name plate. After making sure that the commutator brushes are still raised, cut the rheostat fully "in" and then close the main switch and the circuit breaker (Fig. 110). Cut the rheostat "out" gradually and then "in" again, after which the main switch should be again opened. This procedure causes cur- rent to flow through the generator fields and insures the field coils having a proper residual magnetism. Replace the brushes on the commutator and shift the brush holder, if necessary, to bring the brushes to the "neutral" position. Power SniTCn BOARD STORAOt -=- J- Fig. 110. Simplified Charging Circuit After the machine is running and has built up, the brushes should be rocked backward and forward until the point of minimum sparking is found. When the machine is run- ning under load this should be again checked and the position of the brushes shifted again if necessary; lock and leave brushes in this position. To Start the Charge See that the main switch and circuit breaker are open, and that the rheostat resistance is all cut "in." Get the generator up to speed and make sure that the brushes are in proper position and that the oiling rings are working properly. See that the belt has the proper tension ; that is, it should be as loose as possible and yet not slip or tend to run off the pulley with load on. Cut the rheostat resistance "out" until the voltage is a little higher than that of the battery, being sure that the voltmeter needle deflects in the same direction for both generator and battery (see switch No. 2, Fig. 118). This 164 GENERAL RAILWAY SIGNAL COMPANY latter insures that the positive terminal of the generator will be connected to the positive pole of the battery. Close the main switch and circuit breaker and adjust the rheostat until the proper amount of current is flowing into the battery, also adjust the brushes if necessary for minimum sparking. It will be necessary to change the adjustment of the rheostat occasionally as the battery charging increases, in order to maintain the current at the proper amount. To Shut Down To shut down, lower the voltage by cutting "in " the rheostat until the circuit breaker on the switchboard opens of itself and then stop the engine. If no circuit breaker is provided, wait until the current is practically at zero before opening the main switch on Jthe battery. After the machine has stopped, relieve the tension on the belt so as to prevent it from stretch- ing during such time as the machine is standing idle. General Instructions It is hardly possible to give detailed and complete instruc- tions in these pages for locating all the troubles which may arise in the use of such apparatus. The type of machine used for charging storage batteries is so simple, however, that by adhering to the following general instructions, it is believed that satisfactory operation of the machine will be obtained. The generator should be kept, perfectly clean and dry and should not be unnecessarily exposed to dust. This can best be accomplished by throwing a waterproof covering over the machine when not in use. Do not overload the machine. To load the machine beyond the capacity indicated^ on its name-plate is never conducive to best operation, this being the frequent cause of over- heating in the machine, sparking at the commutator, or other troubles. Overheating the • generator may be readily detected by applying the hand to the various parts of the machine; in general a temperature that cannot be borne by the hand is to be considered excessive. An odor of burning varnish is indi- cative of serious overheating, and a machine which shows this symptom should have the load removed at once; rotation of the armature may be continued with the fields de-energized for the purpose of cooling the machine. The bearings should be kept thoroughly lubricated with the best grade of lubricating oil. While the machine is run- ning, care should be taken from time to time to see that the oiling rings are working correctly. Particular attention should be given to the commutator and brushes to see that the former keeps perfectly smooth and that the latter are in perfect adjustment. The commuta- tor should assume a dark brown, glossy appearance, if proper brushes are used and are kept from sparking, and if the ELECTRIC INTERLOCKING HANDBOOK 165 capacity of the machine as indicated on the name plate is not exceeded. The condition of the commutator and brushes may- be regarded as the best barometer of the condition of the generator. The free use of lubricants on the commutator is not recom- mended. In cleaning the commutator a tightly woven cloth (free from lint) or chamois skin, should be used and the commutator then wiped with a rag which has a little vaseline on it. To fit the brushes to the commutator draw No. 00 sand- paper under them, smooth side to the commutator, as shown in Fig. Ill, the brushes to bear on the sandpaper only when * HANDLE COMMUTATOR Fig. 111. Method of Fitting Brushes to Commutator it is being drawn in the direction in which the surface of the commutator will run when the machine is in operation. After the brush is shaped to the commutator finish up with No. sandpaper and then carefully clean the commutator and brushes of all particles of dust or grit. The brushes shipped with the machine are ordinarily best adapted to the work and other brushes are liable to cause trouble. A little oil may be applied to the brushes should they become dry and noisy. If the armature or field coils of the generator should become wet, they should be thoroughly dried out before running the machine under load as the moisture is liable to damage the windings. The coils of the machine may be dried out by baking in an oven at a temperature of 240 degrees Fahr. for several hours, or if an oven is not available they may be dried out by placing near the fire. Another method is to run the generator for several hours without exciting its field. 166 general railway signal company Generator Fails to Build Up One of the common troubles which occiirs in the operating of generators is the faOure of the machine to build up. This failure may be generally attributed to one of the following 1. Open circuit due to a broken wire, faulty connec- tions, brushes up, fuse blown, open switch, etc. 2. Reversed connections in field circuit or reversed direction of rotation. 3. Excessive resistance due to poor brush contact. Brush contacts often have an excessively high resistance when generator is first started, and a momentary pressure of the fingers on the brush or brushes may enable the machine to build up. 4. Weak, destroyed or reversed residual magnetism. To restore residual magnetism send current from battery through the fields in the proper direction. 5. Brushes not in their proper position. 6. Short circuit in the machine or in the external circuit. R. S. A. SPECIFICATIONS FOR ELECTRIC GENERATOR (1910) Material (a) The generator shall be shunt woimd, self-excited, shall have self-oiling bearings, carbon brushes, rheostat, and when belt connected, a belt tightener, sub-base, and pulley. (b) The normal or rated speed shall not exceed fifteen hundred (1500) r. p. m. except when direct connected to an a. c. motor or steam turbine. (c) The generator shall have a continuous current capacity equal to the eight (8) hour rate ( ampCTe) of the battery, at a voltage equal to the maximum voltage ( volts) of the battery on charge, without a rise in temperature in any part exceeding seventy-two (72) degrees Fahr. (40° C.) above the tem- perature of the surrounding atmosphere. id) It shall be so woimd that its voltage at the con- tinuous current rating given above, may be varied by means of a field rheostat between the minimum and the. maximum charging voltage of the battery. (e) The generator shall be capable of supplying for four (4) hoiu^ a current output twenty-five (25) per cent, in excess of the continuous current capacity referred to in above without a rise in temperature in any part exceeding ninety (90) degrees Fahr. (50° C.) above the temperature of the surroimding atmosphere. (/) It is imderstood that the temperature of the sur- rounding atmosph«% is to be based on seventy-seven (77) ELECTRIC INTERLOCKING HANDBOOK 167 degrees Fahr. (26° C), but should the temperature vary from this, corrections shall be made in accordance with the recommendations of the American Institute of Elec- trical Engineers. (g) The current output of the minimum allowable gen- erator shall be that required for the operation of two (2) switches simultaneously. ^ (h) With the brushes in a fixed position, the generator shall be practically sparkless under all operating condi- tions, as outlined above. (i) These generator specifications describe a machine which, in normal power interlocking service, will have an ample overload capacity to meet general requirements. 168 GENERAL RAILWAY SIGNAL COMPANY # < (N (N (N CJ iM P. il Is > •' ^ ^ 2 S; * a oococ 1311 X > S o 5 o •:; a ELECTRIC INTERLOCKING HANDBOOK 169 H 1 u 1 si| ^^?g8 s 1 5SS§§ 1 g .a lootloo § weoco-*-* 8 1 Ncowweo 1 1 lilili 1 ^ (NW-*®® 1 « H is o i 5 8 d o 1 00 00 00 00 OS Q 1 ««««■* O si 1 OOO^J-^-^ 1 « 1 22^ < NCINMM i 6 >ot~o»oo £g§s 1.00 2.50 3.25 GASOLINE ENGINES General Description GASOLINE engines, used in the charging of moderate sized storage batteries, are generally of the single cylinder four cycle type, water cooled and equipped with the "Make and Break" electric ignition. The vertical type engine is lubricated by the crank dipping into an oil bath in the base of the crank case; oil and grease cups are further provided for lubricating parts not so cared for. The operation of the engine is maintained at a constant speed by either regulating the ' mixture of gasoline vapor or by varying the number of power impulses as soon as a certain A-Circula+ing Tank D-Ven+ B-Re+urn Pipe E- Drain Pipe C- Supply Pipe F- Valve C- Elxhaust Pipe - Engine +0 Exhaust Pai Fig. 114. Water Connections for Gasoline Engine Using Cooling Tank Fig. 115. Water Connections FOR Gasoline Engine Cooled by Running Water speed is exceeded ; the engines so controlled are known as the "Throttling Governor" or the "Hit and Miss" types, respect- ively. In a common type of engine used for this work, a pump supplies gasoline to a reservoir, an overflow pipe being con- nected with the reservoir to maintain the gasoline at a uniform height. At the proper time in the cycle of operation, the engine piston sucks air through the air inlet passage and at such a velocity that gasoline is picked up from the reservoir and drawn through an adjustable nozzle into the cylinder head, the gasoline mixing with the air to form the required explosive vapor. ELECTRIC INTERLOCKING HANDBOOK 171 Location of Engine In locating the engine, at least two feet should be left on all sides of engine for convenience in starting and for having sufficient room to make necessary adjustments and repairs. The gravity system of circulation is generally used for the cooling water. With this system, the tank for the cooling water is generally placed on the floor, as shown in Fig. 114 ; best results are secured, however, by having the tank elevated enough to bring the bottom above the lower water opening on the engine cylinder. Connections should be as shown, large enough piping being used to permit free circulation of the water. Valves F-F must be inserted in the pipe line to permit drawing off the water from engine in freezing weather without emptying the tank. The gasoline tank should be located outside of the building, Fig. 116. Gasoline Tank Location and with engines equipped with a galsoline pump, the tank should be placed at a lower level than the engine, so that when the engine is idle the gasoline will drain back into the tank. In making the connections between the gasoline tank and engine, care must be taken to wash out all piping and joints with gasoline to remove any loose matter or scale from the interior of such connections. To Start Engine See that engine is properly oiled and that water and gasoline valves are turned on. Pump gasoline into reservoir. Fill priming cock on head of cylinder; this may not be necessary in warm weather. Make sure that spark lever is in "retard" or "late" position, then close switch to ignition circuit. Turn engine fly-wheel in normal direction of rotation. After ignition occurs, remove starting crank, advance spark lever to "early" position and regulate the throttle valve. It 172 GENERAL RAILWAY SIGNAL COMPANY will be found that this last adjustment varies with the tem- perature, requiring much coarser adjustment with cold weather than with warm. Load should not be thrown on the engine until after it is in operation. To Stop Engine Close throttle valve and open switch on battery. If it is freezing weather, water should be drawn off from engine. GASOLINE ENGINE TROUBLES Ignition Troubles Engine misses or fails to start (a) Weakened Batteries. (6) Strong Batteries, but with following defects: 1. Switch in "off" position. 2. Insulation on wire worn, causing short circuit. 3. Circuit open by broken or loose connections. 4. "Make and Break" mechanism inoperative, due to broken spring, bearing stuck, etc. 5. "Make and Break" mechanism contacts fouled. 6. "Make and Break" adjustments incorrect. 7. Broken down spark coil. Carburetion Difficulties Engine misses or fails to start (a) Fuel Supply — tank and pipe line: 1. Throttle valve closed. 2. Tank empty. 3. Tank vent stopped up. 4. Gasoline pump inoperative. 5. Gasoline j)ipe plugged. 6. Water in gasoline. (6) Mixtiu-e too rich : 1. Throttle valve adjustment incorrect. 2. Air passage clogged, (c) Mixture too weak : 1. Throttle valve adjustment incorrect. 2. Spray valve partially stopped up. 3. Intake pipe leaky. Loss OF Compression Engine misses, looses power, or fails to start (a) Improper valve operation : 1. Valves do not lift at proper time ; due to loosening or stripping of gearing on cam or crank shafts. 2. Valves fail to seat properly or too slow; due to weak spring. ELECTRIC INTERLOCKING HANDBOOK 173 3. Worn cam followers, cams, push rods, etc. (b) Leaky piston rings. (c) Priming valve open or leaky. (d) Leak in cylinder head packing. (e) Failure of lubricating system (engine hot) : 1. Oil valve shut off. 2. No oil in oil cups. 3. Oil drained out of crank case (vertical engine). (/) Failure of cooling system (engine hot) : 1. Valve in water piping closed. 2. No water in cooling tank. 3. Water below normal level (gravity system of circulation) . 4. Water piping plugged. 5. Pump out of order (forced circulation). Cannot Crank Engine (a) Engine heated due to failure of lubricating or cooling systems. (h) Crank or connecting rod bearing overheated or seized. (c) Piston overheated or seized. (d) Timing gears broken or jammed. (e) Connecting rod disconnected, broken or bent. (/) Crank shaft broken or bent. (g) Water in pump frozen (force system of water circu- lation). Mechanical Difficulties Engine misses, looses power, or fails to start (a) Externally apparent : 1. Valve spring weakened or broken. 2. Valve stem bent, broken, or gummed. 3. Valves leaky (carbon on seats). 4. Valve stem and cam-follower always in contact (no clearance). 5. Muffler or exhaust pipe obstructed. (b) Internally apparent: 1. Cylinders or valves carbonized. 2. Piston rings gummed or broken. 3. Leaky piston rings, slots in line. 4. Cam head worn, shifted or broken. 5. Piston head or cylinder wall cracked. 6. Piston rings and cylinder wall scored. Loss of Power Without Missing (a) Ignition system adjustments wrongly set. (6) Carbureter adjustments wrongly set. (c) Lubricating system operating imperfectly. (d) Cooling system operating imperfectly. (e) Poor valve operation. (/) Batteries weakened, giving poor spark. 174 GENERAL RAILWAY SIGNAL COMPANY ig) Mechanical difficulties, such as worn valve connections, etc. (h) Intake pipe leaky. (i) Muffler or exhaust obstructed. (j) Engine bearings overheated. EDITOR'S NOTE Above articles based on data furnished by Fairbanks-Morse & Company. R. S. A. SPECIFICATIONS FOR GASOLINE ENGINE WITH FUEL AND WATER TANKS (1910) 1. Engine (a) The recommended brake horse power of the gasoline engine shall be not less than one and three-fourths (1%) times the kilowatt capacity of the generator at the maxi- mum voltage and the eight (8) hour charging rate. (6) The engine shall run without injurious vibration and shall operate continuously at Manufacturer's specified capacity for a period of sixteen (16) hours without injurious heating in any part. (c) Regulation in speed shall be within three (3) per cent, from no load to full load and the regulation as re- corded on the voltmeter for a given current shall not vary more than two (2) per cent, between impulses. (d) Electrodes on the engine for electric ignition shall be tipped with platinum or an equally serviceable material. (e) Manufacturer's standard exhaust muffler shall be provided. (/) Engine and accessories shall be acceptable by and installed under the rules of the National Board of Fire Underwriters and the attached requirements of local authorities. (g) Engines of twenty-five (25) horse power or less shall not exceed a speed of four hundred (400) r. p. m. 2. Tanks (o) Gasoline tank of gallons capacity shall be furnished. Fuel and cooling tanks shall be made of iron or steel with brazed or riveted seams. (b) Tanks shall be galvanized after they are put together. (c) For tanks either for fuel or water, selection shall be made, when practicable, from the following table: Gallons capacity Inches in diameter Inches in length Gauge metal Head Body 66 18 68 14 16 120 24 66 12 14 500 36 120 10 12 As a guide in ordering tanks, it is good practice to con- ELECTRIC INTERLOCKING HANDBOOK 175 sider that it will require one-tenth (Vio) of a gallon of gaso- line per horse power hour for gasoline engines. (d) For cooling, the minimum of free running water should be not less than ten (10) gallons per horse power hour, and for the circulation tank system not less than fifty (50) gallons per horse power. (e) Sufficient piping shall be furnished to locate the gasoline tank feet from the engine. (/) Unions in all piping shall be equipped with ground brass seats. (g) Unless otherwise specified, an iron or a steel cooling tank of sufficient capacity for a continuous run of ten (10) hours on one (1) filling, with connections and removable cover, shall be furnished. Connections between engine and tank shall be arranged for convenient and complete drainage of the cooling system, for independent drainage of the engine and tank, and to conduct all waste water and steam to the outside of the building. (h) When engine is installed in sanle building with storage batteries outside air intake shall be provided. SWITCHBOARDS a a o ■^ 3 pq o o Q CO (M (N '^ ^ 73 s .s « ^ M ii £f -^ i § g S O) 1) S S 6 o o o H H H ' L-,9 - .-*■ sBL^r^rl : ! 7 2 2 4 ELECTRIC INTERLOCKING HANDBOOK 177 li ■^. • fc.2'0'0'0'0 fee'"' i?'^'^'' t2 .S t7 c3 M ti f-t • ^ • a> «i o » g J- g S'2'g >(N >co^^^-^ — ©«J«ooS oj "^ aj S S S £ S S 178 GENERAL RAILWAY SIGNAL COMPANY I „L - .9- » .2 • ri |€>raii®:^s 00 -t lipllHHSH-c^iE 1 iiisiiiii|ftiii -C^S"" 1 -"••'•«■ «■ IM! ' to Si [(^(^^;j}4K>i=;;5 1 J -1 4 «0 4 o1 O 00 o ELECTRIC INTERLOCKING HANDBOOK 179 $ = §•1 1 1 i^-i*! 1 1 OO 0^OoP^^'-5'-'OO'-^i-5PhChCOOO ^^ rt ^ t^ t^ t>. t^ r-l —I l> t^ t^ t^ —I rt ,-( ,H = 1 I&&I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I I I I I M i I I M I I I I I I I I I I i I I I I I I I I I I I M I I I I I I I I I I I I I I I I I I I I M I I I I I TTTT7TTTTTTTTTTTT7TT7 CJ2iCHt-3>-HpHCHi-3>Jt-3iJiJi-3i-3i-3h-5h-3tJ»Ji-5»-3 MMcocoPoeoeococoeceocoeoeooococceoeoccco M I M M M I I I I I I I I I I I I 2i £i si 2i si fij si ?^ S5 ?5 1:^ 2i tf ^5 25 2J p::? Ph si P2 Ph I I I I I I M I I I I I I M I I I I i si si SJ si k^ si si ►^ hJ J h^ si Pi Pi 25 25 SJ 1-3 1-3 J .-: Ph J H^ C:J Pi .J O0O00O3OM0OO0»OO«OOO0O0COO0O0O0O0O0O0O0C>(Mt^t^(N(N I I I I CO ro cc cc 3 e4 s3 a> 3 P3P300 'o'o'o'o o O O O O 01 O G o o o c ki k< bi u . . X X X X X X X X X X X X X X X X X X X M c» 555555555555555555552 M 00 lO CD i« »0 «0 ^^^^Tj(,i,ico > > > > •^ -^ -^ -^ -^ ^ 1^ U U t-i u __.^^_ i; O O O O © 4»l»0«00000«««0 Fig. 131 Lighting Panel with Three Double Pole, Single Throw Switches Fig. 132 Lighting Panel with Ten Single Pole, Single Throw Switches Fig. 133 Lighting Panel with Five Single Pole, Single Terow Switches ANO One Double Pole, Double Throw Switch- Fig. 134 Lighting Panel with Two Double Pole, Double Throw Switches Fig. 135 Lighting Panel with Four Single Pole, Double Throw Switches SECTION VII INSTALLATION AND OPERATING DATA FOR ELECTRIC INTERLOCKING MACHINES COVERING INSTRUCTIONS FOR INSTAL- LATION AND MAINTENANCE; ALSO DATA FOR THE APPLICATION AND OPERATION OF LEVER LOCKS INSTRUCTIONS COVERING THE INSTALLA- TION AND MAINTENANCE OF THE MODEL 2 ELECTRIC INTER- LOCKING MACHINE Shipment BEFORE shipment the interlocking machine is assembled complete in every detail and subjected to a rigid electric and mechanical test. It is then partly disassembled, the levers, lever tappets and locking, the legs and lower tiers of locking plates (if furnished) being boxed separately from the body of the machine. This latter is then divided into sections of approximately forty lever spaces and boxed on skids for shipment. Before boxing, all machined parts are wiped dry and coated with vaseline to guard against the effects of rust during transit. Storing Upon the receipt of the machine it should be stored in a dry place. If some time passes before the machine is set up and there is any chance of its different parts rusting, these parts should be wiped dry and recoated with vaseline. Installation The first step in the assembly of the machine is to bolt the sections to their supporting legs and the various sections to each other. The legs are numbered and the machine beds marked to correspond. Extreme care should be taken in shimming up under the legs to insure accurate alignment of the bed and an even distribution of. the weight on the sup- porting legs. Failure to do this, especially in a large machine, is very likely to result in binding between the various parts of the mechanical locking. The second and third tiers of locking plates, if used, should be assembled on the machine, care being taken to place the templet furnished for the purpose in the horizontal and vertical locking slots before doweling the locking plates to their sup- port. Never file the screw holes when mounting' these plates since this is not necessary if the bed has its correct alignment. To permit of the plates being placed in the same location as when the machine was assembled in the factory, the second tier of plates are numbered 1, 2, 3, etc., from left to right, and the third tier lA, 2A, 3A, etc., also from left to right. The locking should then be assembled in the locking plates and the lever tappets placed in their proper positions. Each locking dog is stamped with the number of the tappet with which the dog is to engage and the locking bars with numbers to correspond with the slot in which they are to be placed, these slots being numbered in sequence from the top of the 186 GENERAL RAILWAY SIGNAL COMPANY CABINET Fig. 136. Model 2 Unit Lever Type Interlocking Machine ELECTRIC INTERLOCKING HANDBOOK 187 Fig. 137. Model 2 Ixterlocking Machine 188 GENERAL RAILWAY SIGNAL COMPANY locking bed to the bottom (thirty-two slots per tier of locking) . Each tappet is stamped with the number of the lever to which it is to be attached. ^_ The levers should then be placed in their respective guides, Wnd worked back and forth to insure that they operate freely, that they are checked at the normal and reverse indication points, and that they can be moved to the full normal and full reverse when indicated. (Signal levers are not indicated on the reverse movement.) The circuit controllers and tappets should be carefully fastened to their respective levers, and the levers tried for freedom of movement with all working parts connected. The buss bars, buss wires and the connections between the individual polarized relays, which have been separated during shipment, should be securely connected by joining the short leads provided on the machine for the purpose. Testing A careful test should be given to the mechanical locking by setting up the various routes in accordance with the track plan or manipulation chart, testing the various levers in the route to see that they are locked and likewise testing all levers which conflict with the given route. This will insure that none of the locking parts have been omitted in assembling. When wiring up the interlocking machine it is well to check up the controller contacts to see that all special contacts called for by the wiring plans have been provided. The lever and its connections will be checked up as the individual functions are tested out; i. e., the completed opera- tion of the function normal and reverse, shows that the lever wiring is correct, its controller springs making good contact, that the indication magnet operates properly, and if the func- tion is a switch, that the indication selector also is giving proper operation. If desired, a check can be secured on the polarized relays by making the cross protection tests described on page 94. Maintenance The maintenance of the interlocking machine principally consists in keeping the machine cleaned, all connections tight, and of wiping with an oiled rag at stated intervals such parts as are liable to rust. When cleaning or oiling the locking, it should not be re- moved from the interlocking machine. Use only high-grade oils, such as "3 in One," "Hydrol" or "Polar Ice." Commercial fuse wire should not be used to replace the fuses furnished with the machine, since commercial wire is not carefully graded and may carry a much larger current without melting than the fuses secured from the manufacturer. As a general statement, it may be said that the operation of the various functions is a good check on the condition of the ELECTRIC INTERLOCKING HANDBOOK 189 interlocking machine, since the completed operation of the various functions gives assurance as to the integrity of all parts of their operating circuits. It is well, nevertheless, to antici- pate the possibility of loose connections, etc., and at stated intervals to make inspections of the different connections, Fig. 138. Model 2 Unit Lever Type Interlocking Machine. Equipped with Spring Combination Board Note location of polarized relays, buss bars and fuses. contacts and various mechanical parts on the interlocking machine to insure that all parts are kept in the best condition. As mentioned above, the operator may assure himself as to the constant integrity of the cross protection by means of the simple tests described on page 94. 190 GENERAL RAILWAY SIGNAL COMPANY EH rrp= I? 4= X E X 4= 4= JaAO t CO 5? y ^ I 1 t I 1 1 i !? •* •9 CO 1 s 2 1 ^r^ t 9 III -I 1 g OS 1 « • - •-» : . : : X . o ■ f^ . a ■ ; rb'tbo olcb a _ ■ : : : lb tblcblbiblcb o ; ■ ■ ■ : 1 1 lb 1 lb If » 2 . I 1. I. cb'tblb:Io!b n ■ 9 lb rt< lb 1 CD lb Icb to d; olcb 8? CO < ■ I ? tP 2 % )% :» I& > % 1% <% 1* » CO^ i CO lb tb 9 9h totblt mi 9 tb JO OK # ■* -"t •<* Id H- oj^ . CO CO q =|. CO l^» 2 (N CO o 00 2 CO 2 ! 2 2 + i ! (N ! 0» 2 + M ^1+- t ■* ! + CO c ■* c i; ■<*< 3 sjaAai JO ON " - <© i-l S a E E § !\ GO § E E s ^ as § i 1 1 2 S; ocn 1 ELECTRIC INTERLOCKING HANDBOOK 191 X L a o o 4- « L 1= r ^^ •a 4= e IE i r Rf 4» ?- 00 coico 1 ^1^ ^tb b 11 S3 ^^9 tj^|9 VopVt,J> i 1 «• 1 •i ■ V ; ;: •1 r • 1 -i .j . 1 i i ^ ;| ; ;j ; : TiTltiTit •-> ■| ■ : :| :! J : J J J J J m. ? w - • '■ \ \ tit bb ^^^^ to b b b ib J J J o 1^ k 1* 1* b'b b lO lO u~ -^ -C X X aOjOpop Sppo^|Sp!p b :b b lb « t^ ?hrn -J to .to t:- b b !ry?v^ y^^^b ^JcEoV^ w lb to Bohop »0|«0|«D|0 b btblbltblb b|tb bjtbb b|tbtb!tbb Q U3 « to to b b|tb_b to b t» tbb ^'^■^ '--%'^^'t\ ^|!c!! ?5f cb b o tb to ^^'^^'^ "rW"^^ X X !c X X X X X X X X X op ob b L. ^ ^ ^. .^ .^ -^ -^ -' ~ i' CQ to to X 3p X t7 7^'^ J7Tn TJjj? jVVjII < b b b b T ^ ^ ^y ^ ^^ :: t>- 00 00 » 00 00 "h 05 05 »| 22 22 •-I =|: -1 rH H I— 1 - |P IN O "M (N + + o 31;? + + o'c 22 f 32 i 53 Hi l>;X 1 -V - ?2 ?2 1 8aaA9i I g|« JO -ox 1 ^ to operate the switch by power, the tests on the switch machine should be carried on under the protection of the operating lever, whenever the ELECTRIC INTERLOCKING HANDBOOK 205 conditions are such that the leverman can readily receive and act on signals given him by the man on the ground. On the rare occasions when it is not practical to conduct the test under the control of its lever, power may be applied locally by taking both control wires off from their respective binding posts (for contact springs U4 and U5, Fig. 147) in the pole changer, and having first connected spring Ug with a short piece of wire to the open control contact spring (spring U4, Fig. 147), current may be sent through the motor by plac- ing the energized control wire in connection with the other control contact spring (spring U^, Fig. 147) ; with these con- nections the mechanism will be brought to rest upon the com- pletion of its movement without shock. Reverse these con- nections to secure operation in the opposite direction. After the machine is completely adjusted, safety requires that it should be operated from the interlocking station sev- eral times, making sure that with the lever in its normal posi- _|g— -%-1^ TAP H \* ^e" DRILL A Fig. 148. Drilling for Pins Qi and Q, in Lock Rod K tion the switch points will correspond with their position as shown on the track plan. Maintenance 1. Mechanism. "When inspecting the switch machine always note the posi- tion of the lock plunger relative to the face of lock frame. If it is not flush with the outside face of the lock frame, make sure that stud F is in the corner of cam crank E. With the switch adjusted correctly and the stud F at the end of its travel, there are two conditions which would be responsible for the plunger not reaching its proper position. First — The rails may have shifted and altered the throw of the switch points, which will put an unusual strain on the switch machine and prevent the full movement of the lock plunger. This will be determined by operating the switch by hand. Second — The detector bar may have been thrown out of adjustment by the shifting of the rails, this preventing the generation of the indication current. Necessity for readjust- ment is determined by disconnecting the bar, placing it in proper position and the switch machine in cither extreme position; if it is not possible to replace the pin O without 206 GENERAL RAILWAY SIGNAL COMPANY moving either the machine or detector bar, the connections should be readjusted. On each inspection examine the friction clutch to see that it slips properly on overload. 2. Motor. The motor commutator or brushes should not be disturbed unless found necessary. If the commutator becomes dirty, it should be cleaned with chamois skin moistened with oil, any surplus oil being wiped off the commutator by a dry piece of chamois. If it becomes necessary to put a new brush into a motor, the brush after being put in position should be seated to the commutator by drawing thin, fine sandpaper under the brush, at the same time pressing the brush against the commutator; the smooth side of the sandpaper should be against the com- mutator. Use for this purpose "00 Single Finishing Flint Sandpaper." 3. Small Parts. All cotter pins, lock washers, binding posts, small nuts and screws, should be inspected at stated intervals to see that they are not working loose. 4. Contact Surfaces. The pole changer contacts should be kept clean and bright. 5. Oil. Moving parts not exposed to the weather should be well oiled once a month. All parts, the bearing surfaces of which can be reached b^ rain, should be oiled immediately after each storm. The friction clutches should be oiled on each inspec- tion trip. INSTRUCTIONS COVERING THE INSTALLA- TION AND MAINTENANCE OF THE MODEL 4 SWITCH MACHINE Storing Mechanisms LL mechanisms and motors should be placed right side up on timbers to raise them above the ground. A Installation In making the installation, the first operation is the framing of the ties. This should be in accordance with the plan shown by Fig. 149. Unless special features are required, all holes in the tie plate Tl TleNQE TF t ~eO -Jk. TieMQi e'-8' 4/ a i ■tHf JU^ li! HI Hi -— -f- — t" ^ Tie Nf 2 "s i i -i|" — .^--..-^^^_. ^.^^^ 4- , y ii» n» II U 'I Fig. 149. Tie Framing for Model 4 Switch Machine Ties to be cut as shown in dotted lines for electrified roads using third rail. 208 GENERAL RAILWAY SIGNAL COMPANY O ^ O ■^ ^ a m o .S S « ;=! ^ « ^ ,i«! o o ^ H-5 H^ H S o ELECTRIC INTERLOCKING HANDBOOK 209 are drilled before leaving the factory, with the exception of those for the toe and slide plates. These shoiild be so located that when the slide plates, toe plates, and rail braces are in place, the proper track gauge will be rigidly maintained. The switch machine should then be bolted down to the tie plate and the throw and lock rods connected. Adjustments As the switch machine is completely assembled in the factory and all parts adjusted to meet the conditions under which the mechanism is to operate, there is very little in the way of adjustments necessary to be made. After the machine is wired up, before making any adjust- ments which may be required, the brushes should be raised from the motor armature. 1. Throw Rod. The nuts on the throw rod must be placed so that the switch points will be brought up against the stock rail snugly, but not screwed up far enough to put any unnecessary strain on Fig. 151 Fig. 152 Fields in. Series. Fields in Multiple. WiKiNG FOB Motors, Model 4 Switch Machine the rod. Under normal conditions, with the throw rod adjusted as above, a single switch or derail should permit of hand operation, by using the crank provided for the purpose. If it is not possible to do this, steps should be taken to get the switch into this condition. 2. Lock Rod. The adjustment of the lock rod should be such that the locking dog Hj or H3 will enter its proper notch in the lock rod I with the switch full normal or full reverse, as the case may be, but will be prevented from entering if a piece of metal one-eighth of an inch thick is placed between the switch point and the stock rail. 3. Detector Bar. To adjust the detector bar, place it in the desired position relative to the top of the rail and adjust the connections to such a length that with the switch machine in its extreme position, pin P may be inserted without changing the position of either the detector bar or switch machine. Check this adjustment with the bar and switch machine in the opposite pt«sition and readjust if necessary. 210 GENERAL RAILWAY SIGNAL COMPANY 4. Clutch,. The nut on friction clutch C, by means of which the com- }>ression of the spring is increased or diminished should be ocked in a position which will enable the motor to operate the switch under normal conditions, but will permit the clutch to slip if there is an obstruction in the switch points. This is determined by starting with the nut unscrewed and gradually tightenii^ it up, until the motor operates the switch \^ithout any slipping of the clutches. Fig. [ rZ.ITL'Jl - ~— } ^o»*^**o^ rtiRE» 4- Majn Common, 153. PoL£ Chaj^geb Wiring, Mod ex 4 Switch MAcmwE Testing The preferred method of testing the operation of the switch mechanism is to operate it by hand by means of the crank provided for this purpose, first making sure that the motor brushes are raised before attempting to move the machine. This method should be employed as a regular practice. If it should become necessary to operate the switch by power, the tests on the switch machine should be carried ou under the protection of the operating lever, whenever the con- ditions are such that the leverman can receive an^ act on signals given him by the man on the ground. On the rare occasions when it is not practical to conduct the test under the control of its lever, power may be applied locally by taking both control wires off from their respective binding posts (for contact springs Qi and Qj, Fig. 153) in the pole changer, and having first connected common post R with a short piece of wire to the open control contact spring ELECTRIC INTERLOCKING HANDBOOK 211 (spring Qi, Fig. 153), current may be sent through the motor by placing the energized control wire in connection with the other control contact spring (spring Q2, Fig. 153) ; with these connections the mechanism will be brought to rest without shock upon the completion of its movement. Reverse these connections to secure operation in the opposite direction. After the machine is completely adjusted, safety requires that it should be operated from the interlocking station several times, making sure that with the lever in its normal position, the switch points will correspond with their position as shown on the track plan. Maintenance 1. Mechanism. Shifting of the rails may prevent correct operation of the switch machine in the following manner : First — By altering the throw of the switch points, an unusual strain will be put on the switch machine which will prevent the mechanism from locking up. This will be deter- mined by operating the switch by hand. Second — The detector bar may have been thrown out of adjustment, this preventing the generation of the indication current. Necessity of readjustment is determined by dis- connecting the bar, placing it in proper position and the switch machine in its corresponding extreme position; if it is not possible to replace the pin P without moving either the machine or detector bar, the connections should be readjusted. 2. Motor. The motor commutator or brushes should not be disturbed unless found necessary. If the commutator becomes dirty, it should be cleaned with chamois skin moistened with oil, any surplus oil being wiped off the commutator by a dry piece of chamois. If it becomes necessary to put a new brush into a motor, the brush after being put in position should be seated to the commutator by drawing thin, fine sandpaper under the brush, at the same "^^me pressing the brush against the commutator; the smooth side of the sandpaper should be against the com- mutator. Use for this purpose "00 Single Finishing Flint Sandpaper." 3. Small Parts. All cotter pins, lock washers, binding posts, smaU nuts and screws, should be inspected at stated intervals to see that they are not working loose. 4. Contact Surfaces. The switch circuit controller and pole changer contacts should be kept clean and bright. 5. Oil Moving parts not exposed to the weather should be well oiled once a month. All parts, the bearing surfaces of which can be reached by rain, should be oiled immediately after each storm. 212 GENERAL RAILWAY SIGNAL COMPANY -^^ yfC- ^•^^p ^^S'' -I ~ .;3 if 1 1 ^£ — 1 a 1 1 1 6 ""1 5 -1 -i 1 ~l J .1 1 -f -i ■s :i J -1 ■-- '--- — -f -1 "1 S —ol r c — fl - J= --■; ._. — -1 ', i -i — ^11 S^ :S S ^ 6 ^ S « m S=. 52;:5-a •^ S. s ■ ¥■-. •^ o ^ « l-i o - f-H Sol ^ ^ I £-3 •> H bC S c : o 2 H ' ^ M c (N ^3 -=" W !^ Q O S ELECTRIC INTERLOCKING HANDBOOK 213 «!:^> ^^ X^"" ;./ ^^ "1 =^ -1 if -J -1 R " — -1 :)i —I ,— o ,_ 1 S -fe -1 — -1 s — 1 — .-s 1 1 — ^ — 1 'S -1 -J ~J -i -1 !o E f! I 1 ~ • !• : ^' X ^ 3 -1 II ■s -- : F<5 - ? = ■s " ° ^ -1 2 V c: « - o ^1 -ffl ._. -5 -| -f -1 -1 1 . 3 t < 1 ~ — 4 ~ — 1 ~ -1 -_i — — 1 -I .-. * ~ -o -■ s Q^ X -^ i =^S 1^1:3" 3J-„sJ.|i|ll|= 214 GENERAL RAILWAY SIGNAL COMPANY OPERATING DATA FOR SWITCH MACHINES Function Operated Operating Current Amp. Operating Time Using Maximum Lengtli Control Wires Seconds Switch Machine, Model 2, Switch or Derail, . . . Switch Machine, Model 2, Double Slip or M. P. Frog, Switch Machine, Model 4A, Switch or Derail, . . . Switch Machine, Model 4A, Double Slip or M. P. Frog, Switch Machine, Model 4B, Switch or Derail,. . . Switch Machine, Model 4B, Double Slip or M. P. Frog, ... 10.0 4.5 7.0 4.5 7.0 2.2 3 3.2 3 3.2 Fig. 156. Diagram Showing Comparative Clearances of Model 2 AND Model 4 Switch Machine Normal location. Rail Section Dimension A Model 2 Switch Machine (See Note.) A. R. A.— Type A. A. R. A.— Type B. A. S. C. E. Lbs. per Yd. Inches Inches Inches 60 70 80 90 100 22y4 231/4 24% 26% 28^4 21 227^6 24 25%6 2613A6 2IV4 22% 241/4 253/4 27V4 Note. — Dimension A is the distance from gauge side of rail to point on cover of Model 2 switch machine equal to height of rail used. ELECTRIC INTERLOCKING HANDBOOK 215 Fig. 157. Diagram Showing Clearance between Top of Model 4 Switch Machine and Contacting Surface of Third Rail. Electric Division, N. Y. C. & H. R. R. R. Z'-S'- s I 1 Fig. 158. Diagram Showing Clearance between Top of Model 4 Switch Machine and Contacting Surface of Third Rail, Long Island R. R. 216 GENERAL RAILWAY SIGNAL COMPANY \Z 3-3 J ! Switch I I Connec+ion, ^ ^. nr ia. LocK Roi 7r ^ (or *•-' 'i<>'iT<>T Detector Bar/ u> vu; — ■-] u Connetion, j> Fig. 159. Dimensions of Model 2 Switch Machine ELECTRIC INTERLOCKING HANDBOOK 217 Fig. 160. Dimexsions of Model 4 Switch Machine for Movable Point Frog or Double Slip Switch SWITCH NX CONNECTION. Fig. 161 Dimensions of Model 4 Swrrcn Machine for Single Switch or Deicail 218 GENERAL RAILWAY SIGNAL COMPANY (Section A-B) Fig. 162. Single Switch Operated by Model 4 Switch Machine (Section A-B) Fig. 16S. Singlb Switch Opkrated by Model 2 Switch Machine ELECTRIC INTERLOCKING HANDBOOK 219 2-8- L^d c m fcb=*1Ml*=',o. o., 1 ►, Hoi -lE^^J l°° °°l i W ? fan c-^ ?-3 V— — — 3 L .. - .. . — B (Section A-B) Fig. 164. Split Point Derail, Operated by Model 4 Switch Machine (Section A-B) Fig. 165. Split Point Derail Operated by Model 2 Switch Machine 220 GENERAL RAILWAY SIGNAL COMPANY .M 1 A — (Section A-B) Fig. 166. Hayes Derail Operated by Model 4 Switch Machine -IZ 4'-7i-- 3^ ^ .a vi ^^ (Section A-B) Fig. 167. Hayes Derail Operated by Model 2 Switch Machine ELFX3TRIC INTERLOCKING HANDBOOK 221 1 1 ^ " i, i i - 2-8 - ' s ^3 I (2=1 - tarf>:«n>= □ f^°"'^""' £ ^ n B » "f : " — > |n« ""1 • (Section A-B) Fig. 168. Whakton or Morden Derail Operated by Model 4 Switch Machine (Section A-B) Fig. 169. Wharton or Morden Derail Operated by Model 2 Switch Machine 222 GENERAL RAILWAY SIGNAL COMPANY (Section A-B) Fig. 170. Single Slip Switch Operated by Model 4 Switch Machine (Section A-B) F19. 171. Single Slip Switch Operated by Model 2 Switch Machine ELECTRIC INTERLOCKING HANDBOOK 223 (Section A-B) Fig. 172. Double Slip Switch Operated by Model 4 Switch Machine (Section A-B) Fig. 173. Double Slip Switch Operated by Model 2 Switch Machine 224 GENERAL RAILWAY SIGNAL COMPANY' (Section A-B) Fig. 174. Movable Point Frog Operated by Model 4 Switch Machine (Section A-B) Fig. 175. Movable Point Frog Operated by Model 2 Switch Machine ELECTRIC INTERLOCKING HANDBOOK 225 (Section A-B) Fig. 176. Movable Point Frog (with Double Slip Switch) Operated by Model 4 Switch Machine (Section A-B) Fig. 177. Movable Point Frog (with Double Slip Switch) Operated by Model 2 Switch Machine 226 GENERAL RAILWAY SIGNAL COMPANY hKhfl'I'I'H (/)5 ELECTRIC INTERLOCKING HANDBOOK 227 c o u si 228 GENERAL RAILWAY SIGNAL COMPANY ELECTRIC INTERLOCKING HANDBOOK 229 'I HOOK Bolt ^4 Fig. 181. E. Z. Motiox Plate Rail Clip, Hook Bolt Type Fig. 182. E. Z. Motion Plate Rail Clip, Web Bolt Type • c > h — c J @ « — i 1- ^ PV..^ ^ < D > 77) * D ► Fig. 183. Long Motion Plate "A" Fig. 184. Short Motion Plate "B" DIMENSIONS OF MOTION PLATES ' 'A" AND 'B" Type of Motion Plate Dimensions in Inches 1 c D E . 1 F G Overall Length of Motion Plate Distance Mo- Stroke of tion Plate Motion Moves After Plate Total Rise j Above Rail Total Rise of Motion Plate Rise Above RaU *A 9V2 6 2 1 % tA 12 7% 3% : 1 % tA 12^2 SVa 2% 1^6 1%6 *B 9% 4V2 1%2 2%2 tB - T0% — 6 iy2 iVi * Two rivet holes, t Three rivet holes 230 GENERAL RAILWAY SIGNAL COMP.\NY ELECTRIC INTERLOCKING HANDBOOK 231 Fig. 188. Dimensions of Model 5 Form A Switch Circuit Controller for Selecting Signal Circuits Four circuits normal or reverse, or two circuits normal and two reverse. Fig. 187. Section of Adjusta- ble Cam for Model 5 Form A Switch Circuit Controller (Fig. 186). 232 GENERAL RAILWAY SIGNAL COMPANY" Fig. 188 Fig. 189 ^ ^^ P cm Fig. 190 Fig. 191 d5ll3iS©» Fio. 192 Fig. 193 Fig. 194 Connections ntou Switch Point to Switch Circuit Controi.leb ELECTRIC INTERLOCKING HANDBOOK 233 Bridge End Shore End Fig. 195. Bridge Circuit Closeb Ten way, controlling ten circuits. DIMENSIONS OF BRIDGE CIRCUIT CLOSERS A B c D E F 1 G H ! J K L M In. In. In. In. In. In. i In. In. In. In. In. In. 6 way 10 way 12 way 18J 26 18i 61 7 14i 22i 141 2 8 2 4i 4* lU lOil 14S 22 14J 19 24i 19 f i 7i 8i 7i If 41 If Note. — Twelve way circuit closer is furnished with two tiers of six con- tacts each. Operation of Bridge Circuit Closer The G. R. S. bridge circuit closer with centering device is shown in Fig. 195. In the operation of closing, the bridge end is first caused to approach the shore end with its centering arms thrust forward. When these come into contact with the shore end, the latter is brought into proper alignment, the bridge end continuing its forward movement until they abut ; the blades are then forced to enter the jaws, thus making the desired contact. The centering device will take care of any horizontal mis- alignment up to one and one-half inches. When this is apt to be exceeded, the circuit closer should be attached to the rails in such a manner that when the rails are lined up 234 GENERAL RAILWAY SIGNAL COMPANY the circuit closer will be affected in a similar manner. The design of the jaws permits of three-fourths inch movement above or below the normal position. The maximum stroke of the driving member is approxi- mately thirteen inches. Using this stroke, the maximum extension of the blades (three and one-half inches) can be secured with a permissible opening of five and three-eighths inches between tne bridge and shore ends of the circuit closer ; this forces the blades between the jaws two and three-eighths inches. If required, this distance between the bridge and shore ends may be increased to seven and three-sixteenths inches, which will give a contact extension of one and thir- teen-sixteenths inches and force the blades between the jaws for a distance of three-fourths inch. If it is desired to reduce the operating stroke and still retain the maximum contact extension, the maximum opening be- tween the bridge and shore ends must be decreased a propor- tional amount. SECTION IX INSTALLATION AND OPERATING DATA FOR SIGNAL MECHANISMS COVERING INSTRUCTIONS FOR IN- STALLATION AND MAINTENANCE, EN- ERGY FIGURES, CLEARANCES RE- QUIRED, DIMENSIONS AND TYPICAL CIRCUITS; ALSO DIMENSIONS OF MASTS, SPECTACLES, BLADES AND FOUNDATIONS INSTRUCTIONS COVERING THE INSTALLA- TION AND MAINTENANCE OF MODEL 2A SIGNALS Storing Mechanisms A LL mechanisms should be stored in an upright position /A and, if possible, in a dry place, and should not be re- "^ "^ moved from their boxes until they are installed. Avoid disconnecting or removing the motors from the mechanism cases. Installation In assemblying mechanisms which are shipped separately from the pole bearings or in reassemblying mechanisms which have been disassembled for any purpose, the surface of all exposed mechanical joints must be cleaned and smoothly coated with white lead before assembly, to insure that they are water-tight. Whenever it becomes necessary to bolt a mechanism to its pole bearing, see that the semaphore shaft and mechanism are approximately in their "stop" positions. Then rotate the semaphore shaft backwards and forwards slightly by hand while tightening the bolts, to be sure that no binding takes place during the process. When working on a mechanism, the motor door should always be kept closed except when necessary to do work inside of the motor. After a mechanism has been wired, the wire entrance should be sealed to prevent the circulation of air between the inside and outside of the case. Neglect to thoroughly seal may result in trouble due to the probable accumulation of frost or dirt on the circuit breaker parts. If conduit is used be- tween the mechanism case and the pole, the wire entrance or conduit should be likewise sealed. Adjustments All signals are properly adjusted before shipment, the only adjustments ordinarily required in the field being those due to differences in the semaphore spectacles as follows: if the blade is not horizontal when in its stop position, it can be brought to such position by means of adjusting screw A (see Fig. 197). Spring C, adjusted by screw D, should hold block B firmly against screw A, due allowance being made in the spring adjustment for any increase in weight of the signal arm, due to an accumulation of ice or sleet. Fig. 197 shows relation of adjusting screws, spring, block, etc., when used with upper quadrant signals; this will be reversed when ap- plied to lower quadrant signals. Having adjusted the blade to the horizontal position, the circuit breaker frame should, if necessary, be rotated bodily 238 GENERAL RAILWAY SIGNAL COMPANY ELECTRIC INTERLOCKING HANDBOOK 239 a sufficient amount to cause the blade to assume its exact forty-five or ninety degree position in operation. Individual adjustment of the circuit breaker contact springs should not be necessary under ordinary conditions. If required, great care should be exercised to see that all contacts are adjusted to open and close as shown on the circuit plan which accompanies each signal mechanism. In replacing a circuit breaker which may have been removed from the mechanism for any cause, great care should be taken to see that the circuit breaker operating segments mesh prop- erly. Otherwise, it will be impossible for the blade to assume Fig. 197. Section of Clamp Bearing Showing Semaphore Spectacle Adjustment its proper positions in operation except by extreme adjustment of the contacts and circuit breaker. Lubrication See that all moving parts are thoroughly lubricated with 2A Sema- phore Oil which will not thicken in cold weather nor dry up in hot weather. This oil is especially prepared for Signal Mechanisms. It is non-gumming and free from mineral acids. Use an oil can with a 9" curved spout. After lubrication, the signals should be operated several times, in order to work the oil thoroughly into the bearings. The word "oil" on the diagram. Fig. 196, will indicate what parts require lubrication. If the mechanism has become rusty, especial care should be taken to see that all parts are operating freely before attempting to put the signal in service. 240 GENERAL, RAILWAY SIGNAL COMPANY Tests If the signal has been properly adjusted and lubricated it will operate freely. If in doubt as to whether a signal is sufficiently free in operation, a drop-away test should be made as follows. Connect an adjustable resistance in series with the motor. Gradually reduce it imtil the motor vnXi just move the blade upwards. Just before reaching the forty-five degree position, quickly insert sufficient resistance to just APPLY VASELINE TO LOCK DOG. ONCE A YEAR Pr Fig. 198. Oiling Diagram for Model 2A Dwarf Bearing permit the motor to start backwards, moved by the weight of the blade grip. The current which will permit it to start backwards from a given position should be approximately 50 per cent, of the current required to move it up to that position. The same process should be repeated in the ninety degree position or sixty degree, as the case may be. V The si^ial na\'ing been oiled and operated a few times, see that the blade snubs properly in descending and also that the ratcheted main gear (F, Figs. 52 and 56) clicks approximately three or four times in so doing. The nimiber of clicks can be regulated by the adjusting screw on the ratcheted main gear. ELECTRIC INTERLOCKING HANDBOOK 241 Maintenance Ordinarily in maintaining a signal, the only requirements are that the connections be kept tight, contacts clean, and the mechanism suitably oiled and cleaned. Avoid disturbing the commutator or brushes in any way unless found necessary. A commutator in good condition will have a dark glossy appearance. If, however, it should be- come dirty, it should be cleaned by chamois skin moistened with oil, any surplus oil to be wiped off of the commutator by a dry piece of chamois. Use a chamois skin in cleaning the circuit breaker contacts. If it should become necessary to put a new brush into a motor, the brush should, after having been put in position, be seated to the commutator by drawing thin fine sandpaper under the brush while the brush is being pressed against the commutator. The smooth side of the sandpaper should be against the commutator. Use "00 Single Finishing Flint Sandpaper." OPERATING DATA FOR SIGNALS Fimction Operated Operating Current Holding Current Operating Time Using Maximum Length Control Wire Amp. Amp. Seconds High Signal. Model 2 High Signal, Model 3 or 7, High Signal, Model 2A Dwarf Signal, Model 2A, Dwarf Signal, Model 2 or 3, 3.0 3.0 .82 .62 4.0 .14 .11 .23 .23 .17 4 3 6 4 1 242 GENERAL RAILWAY SIGNAL COMPANY ELECTRIC INTERLOCKING HANDBOOK 243 Ho+e, OneU')inch iraxirfiurn vana+ion dlloned either ndy on total height o^maat. TspoTb'Pipe - U-NoH C Shaft Note" T "^ 5v ' -A ?-*^ (t shatt -4 Ui t Shaft b-eI^ -H t Shaft Bottom of 5 Pipe ^Top of BracKet Post, or top chord »f Bruljt -/ rtete; Dislance betnten cefrter of pel* and *rtical t«nttr of shaft to ba not less than 3|'nor more than 4|". Fig. 200. Bracket Post and Bridge Signal Masts R. S. A. drawing 1037, dated 1910. Not*; TnolOmches maximum variation aliened other nay on total height of mast. Base of Rail^ Mote; Distance betneen center of pole and vertical center of shaft to be not lesa than 3|" nor more than 4.|' Fig. 201. Ground Signal Masts R. S. A. drawing 1035, dated I9l0. 244 GENERAL RAILWAY SIGNAL COMPANY 5*.OGE OF TRACKS IS 4-9 1 YYhEH gauge Of TRACKS IS 4-8^ (^ BETWEEK lKACK&-4(<^ OF SlG«t»t F CI FAPANCF BFTV»EEH SISNAL |f i THE CLEARANCE BETWEErt SIGHAL A«D MAXIMUM EOWPMENT UflE KVILL BE i' GREATER. Fig. 202. Diagram Showing Clearance betweex Model, 2A Dwarf Signal and Third Rail, Electric Division, N. Y. C. & H. R. R. R. Twelve foot track centers. Fig. 203. Method of Taping Wires Running from Mast TO Signal Mechanism (see Fig. 199) ELECTRIC INTERLOCKING HANDBOOK 245 Fig. 204. Dimensicws of Model 2A Three Position, Non-Automatic DwAKF Signal, Equipped with Electric Lamp Fig. 205. Dimensions of Model 2A Two Position, Non-Automatic Dwarf Signal, Equipped with Oil Lamp Spectacle R. S. A. drawing 1233, October, 1912. 246 GENERAL RAILWAY SIGNAL COMPANY ELECTRIC INTERLOCKING HANDBOOK 247 Frwrt. Fig. 207. Dimensions of One Arm Model 2 Solenoid Dwarf Signal Spectacle R. S. A. drawing 1233, October, 1912. Shaft. h- '"vprox 23i"- m', 256 GENERAL RAILWAY SIGNAL COMPANY ELECTRIC INTERLOCKING HANDBOOK 257 258 GENERAL RAILWAY SIGNAL COMPANY J &SL ELECTRIC INTERLOCKING HANDBOOK 259 260 GENERAL RAILWAY SIGNAL COMPANY «n «2 ^_ '7> *0. \^ 262 GENERAL RAILWAY SIGNAL COMPANY SECTION X INSTALLATION AND OPERATING DATA FOR RELAYS AND INDICATORS GIVING ENERGY FIGURES FOR, AND DIMENSIONS OF, THE D. C. AND A. C. RELAYS AND INDICATORS USED IN TRACK AND LINE WORK; ALSO DI- MENSIONS OF RELAY BOXES RELAYS AND INDICATORS ENERGY DATA FOR MODEL 1, D.C. RELAYS Resistance Ohms Mil. Amps. Volts 4 110 .425 5 98 .475 9 80 .7 16 62 1.0 25 52 1.275 30 47 1.4 36 44 1.5 50 35 1.8 100 26 • 2.5 300 15.5 4.-5 500 13 6.5 800 11 9.0 1000 10.5 10.5 Note. — Values given in above table are the mimimum on which the relay will operate. Add 10 per cent, for practical operation. Drop away current equals 23 per cent, of minimum operating current. ENERGY DATA FOR STYLE A, D.C. INDICATORS Four way. Resistance Ohma Mil. Amps. Volts 4 147 .59 5 . 135 .675 12 97 1.16 38 56 2.13 50 49 2.45 75 41 3.10 100 37 3.70 200 31 6.20 250 27 6.75 500 18 9.00 1000 14 14.00 Note. — Values given in above table are the minimum on which the indicator will operate. Add 10 per cent, for practical operation. Drop away current equals 33 per cent, of minimum operating current. 266 GENERAL RAILWAY SIGNAL COMPANY Fig. 228. Model 9, D. C. Relay, Shelf Type Fig. 229. Model 9, D.C. Relay, Wall Type DIMENSIONS OF MODEL 9 D. 2. RELAYS Name No. of Fingers A B c D E Model 9 Form A4 Neutral Relay, . . . 4 6A 7A 9 Model 9 Form A6 Neutral Relay, . . . 6 8A 7^ 9 .. Model 9 Form A8 Neutral Relay, . . . 8 lOH 7A 9 Model 9 Form C4 Neutral Relay, . . . 4 6A 7A 9 Model 9 Form A4 Neutral Wall Relay, . 4 6J 6A 8J 5f 4i Model 9 Form A6 Neutral Wall Relay, . 6 8 efr 8i 51 4i Model 9 Form A4 Polarized Relay, . . . 4 6A 7A 9 Model 9 Form A6 Polarized Relay, ^ . . 6 8A 7A 9 Model 9 Form A4 Polarized Wall Relay, 4 6i 6A 8J 51 4i Model 9 Form A6 Polarized Wall Relay, 6 8 6t^ 8i 51 4i Model 9 Interlocking Relay -. . 6A 12tt 8 ELECTTRIC INTERLOCKING HANDBOOK 267 ENERGY DATA FOR MODEL 9, D. C. RELAYS Resistance Ohms. 4 Way 6 Wat 8 Wat MU. Amps. Volts MU. Amps. Volts MU. Amps. Volts 3.5 79 .28 95 .34 Ill .39 4 75 .30 90 .36 105 .42 4.2 71 .30 85 .36 100 .42 5 71 .36 85 .43 100 .50 6 64 .38 76 .46 85 .51 7 57 .40 69 .49 81 .57 9 53 .48 64 .58 75 .68 10 51 .51 61 .61 72 .72 11 47 .52 56 .62 66 .73 12 51 .61 61 .73 72 .87 16 41 .66 49 .7d 57 .92 17 38 .65 46 .79 54 .92 20 38 .76 46 .93 54 1.08 26 31 .81. 37 .97 44 1.15 35 31 1.08 37 1.30 44 1.54 40 27 1.08 33 1.32 38 1.52 46 24 1.11 29 1.34 34 1.57 50 23 1.15 27 1.35 32 1 60 60 21 1.26 25 1.50 30 1.80 68 20 1.36 24 1.64 28 1.91 75 21 1.57 26 1.95 29 2.18 80 20 1.60 25 2.00 29 2.32 90 18 1.62 23 2.07 27 2.43 98 17 1.67 21 2.06 25 2 45 125 15 1.88 18 2.25 21 2.63 150 14 2.10 16 2.40 19 2.85 200 13 2.60 16 3.20 18 3.60 244 11 2.68 14 3.42 16 3.91 300 11 3.30 13 3.90 15 4.50 346 10 3.46 12 4.15 14 4.85 400 10 4.00 12 4.80 14 5.60 500 8.5 4:25 10 5.00 12 6.00 516 8.5 4.39 10 5.16 12 6.19 600 8.5 5.10 10 6.00 12 7.20 670 7.5 5.02 9 6.03 11 7.37 800 8 6.40 9.3 7.44 11 8.80 900 7.5 6.75 8.5 7.65 10 9.00 1000 7 7.00 8 8.00 9 9.00 1500 6 9.00 7 10.5 8 12.00 1600 5.5 8.80 6.5 10.40 7.5 12.00 Note. — Values given in above table are the minimum on which the relay will operate. Add 10 per cent, for practical operation. Drop away cur- rent equals 40 per cent, of minimum operating current. 268 GENERAL RAILWAY SIGNAL COMPANY 5^4-4rray - — T^isi'-enay— H 9^6-8Ttay Fig. 230, Model 9, D. C. Indicators Fig. 231. Three Position D. C. Motor Relat This relay requires the same amount of energy for operation as the Model 9, D. C. Relay. Drop away current equals 50 per cent, of normal operating current. ELECTRIC INTERLOCKING HANDBOOK 269 ENERGY DATA FOR MODEL 9, D. C. INDICATORS Resis. Tower Ixdicators Switch Indicator 4 Way 6 Way 8 Way Ohms MO. Amps Volts Mil. Amps. Volts MIL Amps Volts Mil. Amps Volts 4 101 .40 107 .43 113 .45 101 .40 4.4 94 .42 100 .44 106 .47 94 .42 6.8 75 .51 79 .54 83 .56 75 .51 9 66 .60 70 ' .63 74 .66 66 .60 9.2 65 .60 69 .63 73 .67 65 .60 14 55 .77 58 .82 61 .85 55 .77 20 45 .90 48 .97 51 1.02 45 .90 22 44 .96 47 1.03 50 1.10 44 .96 30 37 1.11 39 1.18 41 1.23 37 1.11 34 35 1.19 37 1.26 39 1.33 35 1.19 40 30 1.20 32 1.28 34 1.36 30 1.20 50 29 1.45 31 1.55 33 1.65 29 1.45 56 27 1.51 29 1.62 31 1.73 27 1.51 92 24 2.20 26 2.39 28 2.57 24 .2.20 100 22 2.20 23 2.30 25 2.50 22 2.20 130 19 2.47 20 2.60 21 2.73 19 2.47 200 15 3.00 16 3.20 17 3.40 15 3.00 300 13 3.90 14 4.20 15 4.50 13 3.90 500 11 5.50 12 6.00 13 6.50 11 5.50 690 8.5 5.86 9 6.21 9.5 6.55 8.5 5.86 1000 7.5 7.50 8 8.00 8.5 8.50 7.5 7.50 Note. — Values given in above table are the minimum on which the indicator will operate. Add 10 per cent, for practical operation. Drop away current equals 33 per cent, of minimum operating current. 270 GENERAL RAILWAY SIGNAL COMPANY 8^6- 6 Way Fig. 232. Relat — Wali. or Shelf Type Fig. 234. Indicating Relay Model 2 Form B, Model 3 Form B, or Model Z Form B, A. C. Relays and Indicators ELECTRIC INTERLOCKING HANDBOOK 271 For Use on 55-110 or 220 Volts, - -25 OR 60 Cycles Name of Device Cycles Maximum Enkrgy Required at Normal Voltage (see Note) 2 Position 3 Position Split Phase Local Line V. A. Watts V.A. Watts V. A. Watts Model 2 Form A Line ^ Relays, with 6 front, 6 back or 12 front con- { tacts, and indicating attachment for tower use J Model 2 Form B Line ' Relays, with 6 front, 2 back contacts, and ■ indicating attach- ment for tower use, . Model Z Form B Line Relays, with 6 front, 2 back contacts, and indicating attach- ment for tower use, . Model 2 Form B Switch Indicator, without - . contacts, Model Z Form B Switch Indicator, without >- contacts, ) Model 2 Form B Tower Indicator, without - contacts, . . . . . Model Z Form B Tower Indicator, without > contacts ) 25 60 25 60 25 60 25 60 25 60 25 60 25 60 12.0 12.0 15.0 15.0 5.5 10.0 15.0 15.0 3.0 5.5 15.0 15.0 3.0 5.5 10,0 10.0 10.0 10.0 2.0 3.0 10.0 10.0 1.5 1.8 10.0 10.0 1 5 1.8 7. 7. 11. 11. 8 8 7 7 5 5 5 5 • 4 4 4 4 6. 6. 6. 6. 4 5 5 ■ 5. 5. 5. 5. 4 4 4 4 Note. — Above energy figures will permit practical operation of these de- vices on a voltage 20 per cent, below normal and are based on a maximum equipment of contacts, including indicating attachment for tower use. Without indicating attachment, with a lesser number of contacts, by spe- cial construction, or by combinations of any of the foregoing, the above energy may be reduced 20 to 50 per cent. Relay must drop away on not less than 50 per cent, of the minimum operating energy. Note. — The above table permits the following line resistance in series with line phase of relay. Volts Cycles Resistance (Ohms) 55 25 75 55 60 100 110 25 150 110 60 200 220 25 250 220 60 300 272 GENERAL RAILWAY SIGNAL COMPANY II V- 6 nay Fig. 235. Model 2 Form A PoLTPHASE Relay '!|Hi"-6V1ay Fig. 236. Model 2 Form A Polyphase Isdicatixg Relay «'5fe-4.way n'Hs-enay' Fig. 237. Side View of Model 2 Form A Polyfhask Relay or Indicating Relay ELECTEIC INTERLOCKING HANDBOOK 273 OPERATION OF THE MODEL 2 FORM A REGULAR POLY- PHASE RELAY, IN CONNECTION WITH DOUBLE RAIL A. C. TRACK CIRCUITS ON ELECTRIFIED DIRECT CURRENT ROADS TwNwI POnCR LINE TRAMSrORMER VOLT AMPERES TOR CURVES MEASURED AT THESE POIMTS O MODEL Z rORM A RELAY ^ 'IMPEDAnCE BOND IMPEDANCE BOND Fig. 238. End Fed Double Rail A. C. Track Circuit \A)LT-AMPERE5 150 \ts no 75 so 25 ~ ~ ~ 1 7 / AVfRAGE BAUASTj/ y y / ^ y ^ ps: tfs: ^ 'ii 300 BAU MT "~~ ^ fOOO 0000 ZOOO 3000 4000 5000 6000 7000 LEMGTH OF TRACK CIRCUIT Ih FEET Fig. 239. Curve Showing Energy Required for Operation on 25 Cycle Current V0LT-AMPCRE3 150 «5 100 75 ^ n 7 7 AV t:ra GE 3ALL AST y y . ^ y' ^ ^ ^.o -^ ss: ^GOOD BALL A5T 1000 Fig. eOOO 3000 4000 5000 6000 7000 8000 LEMGTH OF TRACK CIRCUIT IN FEET 240. Curve Showing Energy Required for Operation on 60 Cycle Current Note. — Volt amperes shown in Figs. 239 and 240 are the total of the volt amperes fed to the track circuit and to the relay local. Relay is equipped with four front and two back contacts. Curves are based on 85 pound rail being used. Good ballast (approximately 10 ohms per 1,000 ft.) consists of rock or gravel ballast, well drained and free from the base of the rails. Average ballast (approximately 5 ohms per 1,000 ft.) consists of a ballast, such as a well drained gravel ballast, covering the base of the rails. Dirt, cinder or badly drained gravel ballast, covering the base of the rails, is considered poor and necessitates the use of much more energy for the operation of track circuits than is shown in the curves. 274 GENERAL RAILWAY SIGNAL COMPAi'TY TABLE SHOWING RELATIVE AMOUNT OF ENERGY RE- QUIRED FOR MODEL 2 FORM A TRACK RELAYS, REGULAR AND QUICK ACTING, WITH DIF- FERENT CONTACT COMBINATIONS Model 2 Form A Track Relays Contact Equipment Relative Amoimt of Energy- Required Regular Regular, 4 front, 2 back, 2 front, 2 back, ..... 6 front, 2 back, 2 front, 2 back, 4 front, 2 back, 6 front, 2 back 1.0 .8 1.4 3.5 3.5 4.2 Regular, Quick Acting, Quick Acting, Quick Acting, ...... Note. — Regular Model 2 Form A relay with four front and two back contacts taken as unity. For energy required by this relay on 25 or 60 cycle operation, see curves on page 273. t3 Fig. 241. Wood Relay Box for Model 2 Form A Polyphase Relays ELECTRIC INTERLOCKING HANDBOOK 275 Fig. 242. Iron Relay Box for D. C. Relays and Form B, A. C. Relays 12l I r- "o|oo ® I I® Csi ^ =5 y ^^/ Fig, 243. Wood Relay Box for D. C, Relays Form B, A. C. Relays 276 GENERAL RAILWAY SIGNAL COMPANY RANGE f RCStSTAttCC 100 OHMS f Pig. 244. CmcDiT for Testing Pick Up and Drop Awat of D. C. Track Relays lANPtRE RAKCC RCi>5TXNCE WO OMWS 1. ^ KJ Fig. 245. CxRcxnT for Testing Pick Up and Drop Awat of D. C. Line Relats SSTAHCC > "-Vi^ 15 0MM5 I 5£ (AMPcneRAncE: -©— 1 VOLT RATIGC CCUU Fig. 246. Circuit for Testing Resistance of Relay Contacts (Resistance equals voltage divided by current ) Notk. — Several readings should be made in above tests and the average taken. The resistance used in Figs. 244 and 245 consists of a resistance with a variable center connection. It should, preferably, have uniformly graduated steps. The resistance used in Fig. 246 may merely be a imit of such resistance as to protect the instniment. It is recommended, however, that a variable resistance be used if available. If voltages used in above tests are higher than those indicated, the resistances used will have to be increased accordingly. The anuneter for all of the above tests should not have a range greatly exceeding the 1 ampere range indicated above. SECTION XI INSTALLATION AND OPERATING DATA FOR TRANSFORMERS COVERING DIMENSIONS AND RATINGS OF LINE AND TRACK TRANSFORMERS TRANSFORMERS K- C Fig. 247 DIMENSIONS OF TYPE L LINE TRANSFORMERS Size Dimensions (Approximate) A B C 1 D ! E 1 F G H Inch Inch Inch Inch Inch Inch Inch Inch 1 2 3 131%6 ISK 17 12% 13% 15V* 10 lli%o 13% 11 121
^xxyxx>y>^^wy>^'j Fig. 265 Fig. 266 Making T Joints in Solid Wire electric interlocking handbook 303 Making T Joints in Stranded or Solid Wires Remove the insulation from the continuous wire where the joint is to be made for about one and one-fourth inches and the braid for about one inch beyond the ends of the insula-, tion. Remove the insulation from the end of the tap wire' in the same manner as described for joints in solid wire. Lay the end of the tap wire across the bare part of the continuous wire as shown in Fig. 263 and wrap around the continuous wire as shown in Fig. 264, stopping when the insulation is reached. Cut off the surplus wire and solder and tape as described under "Soldering" and "Taping." Fig. 267. Parallel Joints Parallel Joints When two or more joints come side by side, as sometimes happens in parallel wires, one joint should be lapped beyond the other so as to leave at least three-fourths inch of the original insulation between the joints, as shown in Fig. 267. Soldering In soldering it is recommended that an approved soldering compound in stick form, such as Allen's Soldering Compound, be used. Joints should be soldered by pouring melted solder over the joint or, if impractical to do this, the work should be done with a well-tinned soldering copper having sufficient heat to thoroughly heat the entire joint. Never use an open flame for soldering joints. Fig. 268 Fig. 269 Method of Taping » Taping All joints whether for inside or outside work must be taped with Okonite tape (or its equivalent) in the following manner : The tape should first be stretched to insure its laying tight to the wire. Start the tape close up to the rubber insulation (see Fig. 268) and wind with a half lap over the joint and rubber 304 GENERAL RAILWAY SIGNAL COMPANY insulation to, but not over, the braid at the end ; thence back over joint and rubber insulation to, but not over^ the braid on the otlifer end, and then back to where taping was started (see Fig. 269). Warm the joint sufficiently to soften the tape slightly, squeezing the tape down with the hand to make it adhere closely to the rubber insulation and to itself. Black friction tape of good quality should be applied over the rubber tape, using three-eighths inch tape for No. 16 wire or smaller, five-eighths inch tape for No. 14 to No. 10 wire inclusive, and three-fourths inch tape for wires larger than No. 10. Start the tape near the middle of the joint and using a half lap, wind about one-half inch beyond the braid at one end; then back to one-half inch beyond the braid at the other end, thence back and finish near the middle of the joint. In order to make a neat, strong joint, it is necessary to draw the tape tight during the whole operation. See Figs. 254, 258, 262, and 266 for appearance of finished joints. Care should be taken to keep the hands free from oils or grease, as these will injure both the rubber tape and the adhesive qualities of the friction tape. ELECTRIC INTERLOCKING HANDBOOK COMPARISON OF BROWN & SHARPE AND BIRMINGHAM WIRE GAUGES BEOWN & Shahpe Gauge BIRUINQHAM Wire Gauge Gauge Num- ber Diam. in Inches Area Gauge Num- ber Diam. in Inches Area Circular Mils Square Inches Circular Mils. Square Inches 0000 .4600 211600 .166190 0000 .4540 206100 . 161883 000 .4096 167800 .131790 000 .4250 180600 .141863 00 .3648 133100 .104518 00 .3800 144400 .113411 .3249 105500 .082887 .3400 115600 .090792 1 .2893 83690 .065732 1 .3000 90000 .070686 2 .2576 66370 .052128 2 .2840 80660 .063347 3 .2294 52630 .041339 3 .2590 67080 .052685 4 .2043 41740 .032784 4 .2380 56640 .044488 5 .1819 33100 .025999 5 .2200 48400 .038013 6 .1620 26250 .020618 6 .2030 41210 .032365 7 .1443 20820 .016357 7 .1800 •32400 .025447 8 .1285 16510 .012967 8 .1650 27230 .021382 9 .1144 13090 .010283 9 .1480 21900 .017203 10 .1019 10380 .008155 10 .1340 17960 .014103 11 .0907 8234 .006467 11 .1200 14400 .011310 12 .0808 6530 .005129 12 .1090 11880 .009331 13 .0720 5178 .004067 13 .0950 9025 .007088 14 .0641 4107 .003225 14 .0830 6889 .005411 15 .0571 3257 .002558 15 .0720 5184 .004072 16 .0508 2583 .002029 16 .0650 4225 .003318 Note. — 1 Mil. = 001 inch. 1 Circular Mil. = Area of 1 Mil. diameter. 306 GENERAL RAILWAY SIGNAL COMPANY SOFT-DRAWN COPPER WIRE Number B. &S. Gauge Dijuneter Bare Wire mincbes Resistance in OHMS AT 68« F- Weight in Pounds 1 Bare Wire R. S. A. Insulation Per 1000 Ft. Per Mile Per 1000 ft. Per MUe Per 1000 tt- Per Mile 2772 .325 .10 .52 320 1687 525 1 .289 .12 .65 253 1337 423 2233 2 .258 .16 .82 201 1062 358 1890 4 . .204 .25 1.31 126 667 224 1183 6 .162 .39 2.08 79 419 158 834 8 .128 .63 3.31 50 264 116 613 9 .114 .79 4.18 40 209 85 449 10 .102 1.00 5.27 31 166 80 422 12 .081 1.59 8.37* 20 104 61 322 14 .064 2.52 13.31 12 66 50 264 16 .051 4.01 21.17 8 41 32 169 GALVANIZED IRON AND STEEL WIRE Number H. W. G. Diameter In Inches Weights Pounds Resistance pee Max in Ohms. AT 68« F. Weight IN Pounds j Bare Wire Double Braid Weather- proof Triple Braid Weathw- proof Iron Steel E.B.B B.B. Steel Per 1000 ft. Per Mile Per 1000 ft. Per Mite Per 1000 ft. Per Mile .340 4821 9079 2.93 3.42 4.05 304 1607 1 .300 37537068 3.76 4.4 5.2 237 1251 2 .284 33636335 4.19 4.91 5.8 212 1121 4 .238 2361 4449 5.97 6.99 8.26 149 787 163 860 178 940 6 .203 I7li 3237 8.21 9.6 11.35 109 573 126 665 140 740 8 .165 113. 915 750 2138 12.42 14.53 17.18 72 378 89 470 100 525 9 .148 1720 15.44 18.06 £1.35 58 305 76 400 85 450 10 .134 1410 18. 8322. 04 28.46.33.3 b6.04 47 250 66 350 76 400 12 .109 495 933 39.36 31 165 43 225 49 260 14 .083 288 541 49.0^7.44 67.88 18 96 28 145 33 175 16 '.065 177! 332 80.0393.66110.7 11 59 ... ... ELECTRIC INTERLOCKING HANDBOOK 307 HARD-DRAWN COPPER WIRE r Diam- eter Bare Wire in In. Break- ing Weight in Pounds Resistaxce IN Ohms at 68° F. Weight in POUNDS Bare Wire Double Braid Weatherproof Triple BraidJ Weath'rproolj Per 1000 Ft. Per MUe Per 1000 Ft. Per Mile Per 1000 Ft. Per Mile Per 1000 Ft. Per Mile .325 4973 .10 .53 320 1687 377 1989 407 2150 1 .289 3943 .13 .67 253 1337 294 1553 316 1670 2 .258 3127 .16 .85 201 1062 239 1264 260 1370 4 .204 1967 .26 1.35 126 667 151 795 164 865 6 .162 1237 .41 2.14 79 419 100 529 112 590 8 .128 778 .64 3.39 50 264 66 349 75 395 9 .114 617 .81 4.29 40 209 54 283 62 325 10 .102 489 1.02 5.41 31 166 46 241 53 280 12 .081 307 1.62 8.60 20 104 30 158 35 185 14 .064 193 2.20 11.59 12 66 20 107 25 130 16 .051 133 4.12 21.74 8 41 16 83 20 105 COPPER-CLAD WIRE— GRADE "A" Bright, Hakd Drawn Diam- eter Bare Wire in In. Break- ing Weight in Pounds Resistance in Ohms at 60° F. Weight in Pounds j Bare Wire Double Braid Weatherproof Triple Braid Weath'rproof Per 1000 Ft. Per MUe Per 1000 Ft. Per Mile Per 1000 Ft. Per Mile Per 1000 Ft. Per Mile .325 5472 .32 1.70 «3 1546 350 1850 381 2011 1 .289 4798 .41 2.14 232 1226 273 1443 295 1560 2 .258 3804 .51 2.70 184 972 223 1177 243 1283 4 .204 2721 .81 4.29 116 611 140 740 153 810 6 .162 1797 1.29 6.82 73 384 94 494 105 555 8 .128 1187 2.05 10.84 46 242 62 327 71 373 9 .114 984 2.59 13.68 36 192 51 266 58 308 10 .102 780 3.26 17.24 29 152 43 227 51 266 12 .081 512 5.20 27.43 18 96 28 149 33 176 14 .064 >334 8.25 43.60 11 60 19 101 24 127 16 .051 216 13.14 69.40 7 38 15 80 19 102 Note. — Average conductivity, 30 per cent, per cent. Minimum conductivity, 27 308 GEXER.4L RAILWAY SIGNAL CX)MPANY n h si S55 Sao 5 § 8 C tf ;C :£ ^ C c) r< X X CO T-i c o 8 8 g i 2 g r^ C ^ r^ C) c 88 8 § -H -. CO CO ^ Ss N CI o o « 00 X t^ t^ C5 M M X CI N c c c X t 2 ? S 2: S acity. TABLE FOR DETERMINING REQUIRED SIZE OF CONDUIT CovDtTr RUBBEP-CJOTERED CX)PPER WIRE. R. S. A. SPECinCATION-8 J Inside Diam. Area Inside No. No. 1 No. 2 No. 4 No. 6 No. 8 No. 9 No. 10 No. 12 Na 14 No. 16 Indi sq-m. 1 .785 1 1 . 1 2 2 2 3 3 4 4 5 1% 1.77 2 2 2 4 5 5 7 8 8 9 12 2 3.14 3 3 4 7 8 10 12 13 14 15 21 2% 4.91 4 5 7 11 13 15 20 21 22 24 32 3 7.07 6 8 10 16 19 22 28 30 32 35 47 3% •9.62 9 11 13 21 26 30 38 41 43 47 63 4 12.57 11 14 18 28 34 39 50 54 56 62 83 NoTK. — Table based ,^d:h/^ i 'M-^-^ 7"- 5136 11 capping 675' BM Trunking 1667' BM 5i3e 12 Capping 1667 'BM TrunKmg 2333' BM Fig. 270. Trunking Sections Dimensions as shown are for rough sawed trunking and capping before "ghth inch from ,000 hneai feet. surfacing. To determine finished dimensions deduct one-eight each side to be surfaced. Amounts of board feet are for 316 GENERAL RAILWAY SIGNAL COMPANY - JUNCTION BOX Fig. 271. Trtjnking and Junction Box (Construction ELECTRIC INTERLOCKING HANDBOOK 317 13 s- 6, frH 1 s II 10 IT §8 §8 SS i 00 oc t^iO t^iO 1 3 !^ '■' rHrH .-1 OH if c CCC zi ^ « Ms Q Ii « 0) Q 1-1 00 c bC-^ 03' %. \ 1« r Q ss c c il 0" 11 coco ^1 Ph 00 — ,- cc — ,~ --v— — Y~ ^fe p OQ ,_, ^^ V^M i^ r^ 10 !:- to 3 : ? ' ? • X o« bCO 1 1 . l«- ;^ Ii "3 6,M J3 C UO a c IS I fcl c i tJ c \ 1 ■ 11 II il It i: H i a 3 t S 3 gj H > _^ X X Jir^ '-D ^ :1 Z _c .u c C"" <1 3 3 a P5 •^ cs CI (N ►-5 io ^ s ^ % _^ d _^ _^ ^ _^ IS • •*3 ♦3 "C i 1 c i 1 c 1 8 -^ M '"' '" '"' ^ ^er cent, voids. Tables bas^ on 1 sack cement =1 cubic foot. 4 sacks cement =: 1 barrel. Above quantities may vary 10 per cent, in either direction, depend- ing upon the materials used and the compactness of the concrete. DcAa for above tablet from the Umversal Poriiand Cement Company. ELECTRIC INTERLOCKING HANDBOOK 325 R. S. A. SPECIFICATIONS FOR PORTLAND CEMENT CONCRETE (1912) 1. General These specifications are for making concrete as used in signal construction. 2. Cement Cement shall be Portland, either American or Foreign, which will meet the requirements of the specifications. 3. Sand Sand shall be clean, sharp, coarse, and of grains varying in size. It shall be free from sticks and other foreign matter, but it may contain clay or loam not to exceed five (5) per cent. Crusher dust, screened to reject all particles over one-fourth (V^) inch in diameter, may be used instead of sand, if approved by the Engineer. 4. Stone Stone shall be sound, hard, and durable, crushed to sizes not exceeding two (2) inches in any direction. For rein- forced concrete, sizes usually are not to exceed three- fourths (%) inch in any direction, but may be varied to suit character of reinforcing material. 5. Gravel Gravel shall be composed of clean pebbles of hard and durable stone of sizes not exceeding two (2) inches in diameter and shall be free from clay and other impurities except sand. When containing sand in any considerable quantity, the amount of sand per unit of volume of gravel shall be determined accurately, to admit of the proper proportion of sand being maintained in the concrete mixture. 6. Water Water shall be clean and reasonably clear, free from sulphuric acid or strong alkalies. 7. Measure The unit of measure shall be the barrel, which shall be taken as containing three and eight-tenths (3,8) cu. ft. Four (4) bags containing ninety-fom* (94) pounds of cement each shall be considered the equivalent of one (1) barrel. Fine and coarse aggregates shall be measured separately as loosely thrown into the measuring receptacle. 326 GENERAL RAILWAY SIGNAL COMPANY 8. Density op Ingredients (a) For pipe carrier foundations and reinforced con- crete, a density proportion based on 1 :6 is recommended, i. e., one (11 part of cement to a total of six (6) parts of fine and coarse aggregates measured separately. (by For signal and other foundations made in place a density proportion based on 1:9 is recommended, i. e., one (1) part of cement to a total of nine (9) parts of fine and coarse aggregates measured separately. 9. Mixing (a) Tight platforms shall be provided of sufficient size to accommodate men and materials for progressive and rapid mixing. Batches shall not exceed one (1) cu. yd. and smaller batches are preferable. (6) Spread the sand evenly upon the platform, then the cement upon the sand, and mix thoroughly until of an even color. Add all the water necessary to make a thin mortar and spread again; add the gravel if used, and finally the broken stone, both of which, if dry, should first be thoroughly wet down. Turn the mass with shovels or hoes until thoroughly incorporated, and all the gravel and stone is covered with mortar; this will probably require the mass to be turned four (4) times. (c) Another approved method, which may be permitted at the option of the Engineer in charge, is to spread the sand, then the cement and mix dry, then the gravel or broken stone. Add water and mix thoroughly as above. (d) A machine mixer may be used whenever the volume of work will justify the expense of installing the plant. The necessary requirements for the machine will be that a precise and regular proportioning of materials can be controlled and tl^t the product delivered shall be of the required consistency and thoroughy mixed. 10. Consistency The concrete will be of such consistency that when dumped in place it will not require much tamping. It shall be spaded down and tamped sufl&ciently to level off, and the water should rise freely to the surface. 11. Forms (a) Where necessary, forms shall be well built, substan- tial and imyielding, properly braced, or tied together by means of wire or rods, and shall conform to lines given. (h) For ?dl important work, the lumber used for face work shaD be dressed on one (1) side and both edges to a uniform thickness and width, and shall be sound and free from loose knots, secured to the studding or uprights in horizontal lines. ELECTRIC INTERLOCKING HANDBOOK 327 (c) For backings and other rough work undressed lum- ber may be used. (d) Where comers of the masonry and other projections, liable to injury, occur, suitable moldings shall be placed in the angles of the forms to round or bevel them off. (e) Lumber once used in forms shall be cleaned before being used again. (/) The forms must not be removed within thirty-six (33) hours after all the concrete in that section has been placed. In freezing weather they must remain until the concrete has had a sufficient time to become thoroughly hardened. (g) In dry, but not freezing, weather the forms shall be drenched with water before the concrete is placed against them. 12. Disposition (a) Each layer shall be left somewhat rough to insure bonding with the next layer above; and if it be already set, shall be thoroughly cleaned and scrubbed with coarse brushes and water before the next layer is placed upon it. (6) Concrete shall be deposited in the molds in layers of uniform thickness throughout. (c) The work shall be carried up in sections of convenient length and each section completed without intermission. (d) In no case shall work on a section stop within eight- een (18) inches of the top. (e) Concrete shall be placed immediately after mixing and any having an initial set shall be rejected. 13. Facing (a) The facing will be made by carefully working the coarse material back from the form by means of a shovel bar or similar tool, so as to bring the excess mortar of the concrete to the face. (6) About one (1) inch of mortar (not grout) of the same proportions as used in the concrete may be placed next to the forms immediately in advance of the concrete. (c) Care must be taken to remove from the inside of the forms any dry mortar, in order to secure a perfect face. 14. Finishing (a) After the forms are removed, which should generally be as soon as possible after the concrete is sufficiently hardened, any small cavities or openings in the face shall then be neatly filled with mortar. The entire face shall then be washed with a thin grout of the consistency of whitewash, mixed in the same proportion as the mortar of the concrete. The wash shall be applied with a brush. The earlier the above operations are performed the better will be the result. 328 GENERAL RAILWAY SIGNAL COMPANY (b) The top surface of aU crank, compensator, well hole, lock, dwarf, and high signal foundations shall be rubbed smooth by hand and shall be true to grade and line. 15. Waterproofing • Where waterproofing is required, a thin coat of mortar or grout shall be applied for a finishing coat upon which shaJU be placed a covering of suitable waterproofing mate- rial. 16. Freezing Weather Concrete to be left above the surface of the ground shall not be constructed in freezing weather, except by special instructions. In this case the sand, \ra,ter and broken stone shall be heated, and in severe cold, salt shall be added in proportion of about two (2) pounds per cu. yd. 17. Reinforced Concrete Where concrete is deposited in connection with metal reinforcing, the greatest care must be taken to insure the coatii^ of the metal with mortar, and the thorough com- pacting of the concrete around the metal. ^JTienever it is practicable the metal shall be placed in position first. This can usually be done in the case wh^e the metal occurs in the bottoms of the forms, by supporting the metal on transverse wires, or otherwise, and then flushing the bottoms of the forms with cement mortar, so as to get the mortar under the metal, and depositing the concrete immediately afterward. The mortar for flushing the bars shall be composed of one (1) part cement and two (2) parts sand. The metal used in the concrete shall be free from dirt, oil, or grease. All mill scale shall be removed, by hammering the metal, or preferably by pickling the same in a weak solution of muriatic acid. No salt sMIl be used in reinforced concrete when laid in freezing weather. SECTION XV WRITTEN CIRCUITS INCLUDING NOMENCLATURE OF OPER- ATED UNITS, CIRCUITS, AND WIRES, WITH TYPICAL ILLUSTRATIONS WRITTEN CIRCUITS WRITTEN Circuits, as hereafter described, have been de- signed to overcome the faults in the old method of circuit drawing which developed upon attempting its application to large interlocking installations. A circuit plan for an interlocking, drawn up by the old method, consisted of a track plan, more or less to scale, on which plan symbols of the various pieces of apparatus were shown, placed as far as possible in tneir proper relative posi- tions; such points as should be electrically connected were joined by lines representing wires. While this method has been of great value in the past and still remains so for typical circuits, automatic signal work and small interlocking plants, the plans run into such size when used for large interlocking installations as to practically prohibit its use in connection with that class of work. It is true, furthermore, that a great deal of unnecessary labor is involved in both drawing and deciphering the circuits. For example: The engineer in drawing up such a plan begins with some simple sketches, perhaps using symbols of his own invention. After carefully checking these circuits and assur- ing himself of their correctness, he converts them into the rather elaborate form described above, in which the attempt to keep down the size of the plan is very apt to result in a cramped arrangement of apparatus and a tangle of wires. When the man on maintenance or installation wishes to make use of these circuits, he has to reverse the process and reduce the composite drawing to its simple elements. Written circuits have been designed to eliminate this un- necessary work and especially to secure plans in which the complete circuit for any given switch, sigpal, or other function, can be written on a page of ordinary size without crowding, these pages being bound together in a book which will easily and instantly permit reference to be made to any portion of the wiring of the plant. A set of plans drawn up in accordance with this method involves the following: 1. Location Plan. This shows the relative location of track, interlocking station, switch and signal functions, track relays, switch circuit controllers, etc. Notes, such as for the routing of signal arms, should be included on this plan. 2. Typical Plan of Special Circuits. This shows what is proposed to be accomplished in route locking, etc., these circuits to be drawn up either by the old method, or in "written" form, as desired. 3. Typical Plans of Signal Circuits, Switch Circuits, etc. 4. Special Circuits, made up in ''written" form. These special circuits are separated so that circuits not connected together are kept entirely apart from each other, being drawn 332 GENERAL RAILWAY SIGNAL COMPANY up on separate sheets. This desirable feature causes the "written" circuits to be exceptionally clear and permits their being readily grasped. 5. Detail Wiring Plans. It may be helpful under certain conditions to add to the circuits listed above, detail plans showing the wiring for the indicator group and interlocking machine. In drawing up such circuits it is necessary to use a nomen- clature for naming the apparatus and to adopt symbols to be used in writing the circuits. A nomenclature of operated units and of circuits, which has been used for some time by the General Railway Signal Company and found thoroughly practicable is given on the following pages. On page 337 is given a nomenclature of wires. It is to be understood that this is equally applicable to written circuits or to circuits drawn up by the older methods. NOMENCLATURE OF OPERATED UNITS A — Approach Relay or Indicator. With number as pre- fix, indicating number of principal signal up to which the approach section controlling same leads, as lOA. B — Positive Battery Wire. Used alone where only one battery voltage is in use. When used with H as a suffix (BH) indicates 110 volt battery. When used with L as «a suffix (BL) indicates low voltage battery. When more than one low voltage battery is used with dif- ferent voltage, use number indicating voltage as further suffix, as BI^IO, indicating 10 volt battery. C — Common Wire. Used alone when only one common is in use. When used with H as a suffix (CH) indicates 110 volt common. When used with L as a suffix (CL) indicates low voltage common. When more than one high voltage or low voltage common is used, use num- bers as further suffixes. (CH-1, CH-2. CL-1, etc.) D — Relay or Indicator Controlling the Ninety Degree Posi- tion or Distant Function of a Signal. With prefix indi- cating the number of principal signal which it controls, as lOD, indicating relay or indicaror controlling the ninety degree position of signal No. 10, or signal No. 10 if it is a distant signal in two position signaling. E — Special Relay or Indicator (other than T, D, H, K, or E relays and indicators). With number as prefix indi- cating number of principal unit entering into its control, or indicating principal unit which it controls. F — Relay or Indicator Repeating a Track Relay or Signal. With number as a prefix indicating number of relay or signal which it repeats, as IjOF. FP — Floor Push. ELECTRIC INTERLOCKING HANDBOOIC G — Switch Indicator. With number of signal governing through block in which switch is located as prefix, as lOG. H — Relay or Indicator Controlling Forty-five Degree Position or Home Function of a Signal. W^^^ prefix indicating the number of principal signal which it controls, as lOH, indi- cating relay or indicator controlling the forty-five degree position of signal No. 10, or signal No. 10 if it is a home signal in two position signaling. J — Junction Box or Terminal Board. With arbitrary num- ber as prefix, as lOJ. K — Lock Relay. Used in connection with route or detector locking for interrupting the current supply to switch and derail machines, etc., with number as a prefix, indicating track section affected by it, as lOK. KS — Knife Switch. L — Lever Lock. With prefix indicating number of lever which it locks, as lOL, meaning lock on lever No. 10. LA — Lightning Arrester. LC — Latch Contact. With prefix indicating number of lever, as lOLG. M — Man-hole. With arbitrary number as prefix, as lOM. PB — Push Button or Strap Key. PC — Pole Changing Relay. With prefix indicating number of signal at which relay is located or number of signal controlled by it. S — Stick Relay. Used in connection with route locking. With number as prefix, as lOS, meaning stick relay locking route of signal No. 10, or locking operated units in track section lOT, if separate stick relays are used for each track section. SL — Outlying Switch Lock. With number as prefix indi- cating number of controlling lever. Use arbitrary number if there is no controlling lever. T — Track Circuit. With number as prefix indicating num- ber of track circuit, as lOT, which is also the name of the track relay for track circuit lOT. Note. — The number for Ihe track circuit is taken from the following in the order given : M. P. Frog or Switch or Derail or Arbitrary numbers 01, 02, 03; etc. TL . — Traffic Lock. With prefix indicating number of l6ver Svhich it controls, as lOTL. TP — Telephone. TR — Time Release. With n"umber as prefix indicating principal unit which it releases, as lOTR. V — Electric Slot. With number of signal as prefix, as lOV. XB — Crossing Bell. With arbitrary number as prefix, such as lOXB. 334 GENERAL RAILWAY SIGNAL COMPANY NOMENCLATURE OF CIRCUITS Symboi£ for Operated Units An operated unit (signal, relay, indicator, etc.) is repre- sented by a rectangle with the number and letter of the relay, signal, etc., inside, thus: The forty-five degree mechanism of a three-position is indicated thus: ID 45 And the ninety degree thus: 10 90 Circuit Controllers Operated by Switch Points Closed when switch is normal,. . . Closed when switch is reversed, . . . Closed when switch is normal and locked in position, Closed when switch is reversed and locked in position, ^Switch Number 10 10 Circuit Controllers Operated by Signals Closed at 0° only, Closed at 45° only, Closed at 90° only, Closed at 60° only, Closed between 0° and 45°, .... Closed between 45° and 90°, etc., . . «' Signal Number 10 10 "45 io_ 90 10 "60 10 ELECTRIC INTERLOCKING HANDBOOK 335 Circuit Controllers Operated by Levers N — Full normal position of lever. B — Normal indication position. C — Intermediate position. D — Reverse indication position. R — Full reverse position. Heavy horizontal line indicates portion of cycle of lever through which circuit is closed . N B C D R + I Symbol — ^.^ — z^ —\— •^- ^^— > I 1 I Relay and Indicator Contacts Relay Number Neutral front contact, ,ot Neutral back contact, iot Normal polarized contact, \\o-^\ Reverse polarized contact, ..... |,ot| Intermediate contact on three-posi- tion relay: Closed when relay is ^ deenergized, > lOT -« Time Release Contact Normally closed, ^10 tr^ • Normally open, 10 t r . 336 GENERAL RAILWAY -SIGNAL COMPANY Latch Contact Normally closed, Normally open, . Push Button or Strap K^ey Normally closed, Normalljropen, . Normally closed. Normally open, . Terminal - PB - Knife Switch - KS - 10 J Meaning terminal in junction box No. 10 or on terminal board No. 10. Note. — Small numbers ' written as exponents to the right and above relay numbers, lever numbers, etc., indicate contact numbers. Relay or indicators contacts are numbered from left to right looking toward the relay. Graphical Symbols for Circuit Controllers Operated by Levers Model 2, interlocking machine. ^zM.^ rrW'fir Lever Contact^Numbering Model 2, interlocking machine. BCfTTOM 1 n Top n RCVER5C nORMAL ELECTRIC INTERLOCKING HANDBOOK 337 NOMENCLATURE OF WIRES The matter of primary importance in naming wires is to have a different name for each wire and have it so shown on both the plan and suitable tags attached to the wires : this in order that a wire on the ground may be quickly identified on the plan. At the same time it is highly desirable to have a wire nomen- clature system that is suggestive, so as to reduce, as far as possible, the necessity for reference to plans. On account of the multitude of circuit combinations possible, a system must be rather elastic. With all of the above taken into consideration, the followii^ is submitted as a practical system of wire nomenclature. Note. — Names of wires are shown on plans in brackets, thus: (lOD). Number of cable containing a wire may be written above and at right angles to the wire, thus : o I — Indication Wire. With number of unit which it indi- cates as prefix, as 101. LL — Lighting Wire. N — Normal Control Wire. With number of operated unit which it controls as prefix, as ION. P — Ninety Degree Control Wire. With number of signal as prefix, as lOP. R — Reverse Control Wire. With number of operated unit which it controls as prefix, as lOR. If 10 is a three-position signal, lOR is the name of the forty-five degree control wire. V — Slot Wire. With number of signal as prefix, as lOV. X — Wire going to positive battery through a circuit con- troller on a signal closed in the zero degree position only, with the number of the signal as a prefix, as lOX. Y — Wire going to positive battery through a circuit con- troller on a signal closed from zero to forty-five degrees only, with the number of the signal as a prefix, as lOY. Z — Wire going to positive battery through a circuit controller on a signal closed in the clear position if the signal is a two-position signal, or closed from forty-five to ninety degrees if the signal is a three-position signal, with the number of the signal as a prefix, as lOZ. Wires not covered by the alaove are named as follows : A wire leading from the operating coil of a unit toward battery positive takes the name of this unit, as lOH, meaning the wire from the coil of home control relay for signal No. 10 leading to positive. After passing through a circuit controller, it takes the number "I" as a suffix, as lOHl. This suffix nurnber increases by one as the wire successively breaks through additional controllers. The wire leading from the operating coil to battery negative, takes the name of the unit with the letter "C " as a prefix, as GENERAL RAILWAY SIGNAL COMPANY ClOH, and after breaking through successive controllers is written ClOHl, C10H2, etc. The above method applies directly to simple circuits having no branches, thus: C-i6F-^212yil_,8F-^^51^JtlI (10H1) 14F— B In cases of branch wiring this method is applied directly to the principal circuit — circuit for superior route. The first branch from this circuit takes the suffixes 21, 22, etc., instead of 1, 2, etc. The second branch 41, 42, etc., thus continuing allowing twenty numbers for each branch. BL- BH- 31 OtT ^'t*' I IAI CL j^i^,s' CL [|p]_Cu fc^ll^' CL ttl5L,TR^ CL il22 ^ |M-3r« CL S^ll ^jT^iiyl_ ^^M^-. |5^-iltfi_ LC -iiiH]D- i^j^ JCliL 3F' ii£l .Ml 3Fa (1£D ,o' m. •CM Fig. 274. Section of Location Plan with Special Circuits ELECTRIC INTERLOCKING HANDBOOK 339 ILLUSTRATIONS Illustrative of "Written Circuits" and "Wire Nomen- clature, " is shown in Fig. 274, a section of an interlocking plant with the special circuits used in connection with such an arrangement. In accordance with the instructions given under "Location Plan" on page 331, the track plan with the rela- tive location of signal and switch functions, track relays and the interlocking station with its indicators, relays, etc., is shown. Below the track plan are shown the special circuits drawn up in written form. Referring to the sheets of nomenclature shown on the preceding pages, it will be seen that the circuit '=dT ^=17 -CD •"^^^^ '''^^' ^5) CM .20)iHl22— il^f^ ^ Fig. 275. Signal Selecting Circuit shown at the top is for the control of the annunciator for signal No. 1, this taking low voltage battery through front contacts of the track relays for sections 03T and 02T. Sim- ilarly the control of lock IL takes battery through normally closed contact No. 2 of screw release ITR, the front point of home relay 3F, the front point of contact No. 2 of stick relay IS and the latch contact of the lock itself; the current after passing through the lock goes to the low voltage common wire. Information regarding the operation of this type of special circuit may be had by reference to the Section on Electric Locking Circuits" (page 133). Fig. 275 illustrates the method of writing a signal selecting circuit. This is included principally to show the application of the wire nomenclature to the different branches of the same circuit. The wires of each branch are designated in the same manner as in the principal circuit but with the suffixes 21, 22, 23, or 41, 42, 43, etc., these depending upon the order in which the different branches are taken from the principal circuit. SECTION XVI SIGNAL ASPECTS AND SYMBOLa COVERING STANDARDS ADOPTED BY THE RAILWAY SIGNAL ASSOCIATION SIGNAL ASPECTS AND SYMBOLS R. S. A. PRINCIPLES OF SIGNAL INDICATIONS (1906) (a) On all high signals conferring or restricting rights a . red light shall be the night indication for stop. A yellow light shall be the night indication for CAUTION, and a green light the night indication for proceed. Note. — The word caution to be used as indicating the function of a distant signal. (6) The day indication of semaphore signals shall be given in the upper right-hand quadrant. (c) The semaphore arm in the horizontal position shall indicate stop, inclined upward forty-five (45) degrees, CAUTION, and inclined upward, ninety (90) degrees, PROCEED. SIGNALING PRACTICE AS DEFINED BY THE R. S. A. (1913) Memorandum on the Essentials of Signaling Incorporated in the Report of the Committee on Trans- portation of the American Railway Association, May, 1911. "The reports of various Committees of the Railway Signal Association and of the American Railway Engineering Asso- ciation on the subject of signaling have been submitted to this Committee, with the request that the essentials of signaling be outlined or defined for the future guidance of their Committees. The subject has been carefully analyzed and considered. There are three signals that are essential in operation and therefore fundamental, viz : 1. Stop. 2. Proceed with caution. 3. Proceed. The fundamental, "proceed with caution," may be used with the same aspect to govern any cautionary movement; for example, when : (a) Next signal is "stop." (b) Next signal is "proceed at low speed." (c) Next signal is "proceed at medium speed." (d) A train is in the block. (e) There may be an obstruction ahead. There are two additional indications which may be used where movements are to be made at a restricted speed, viz: 4. Proceed at low speed. 5. Proceed at medium speed. Where automatic block system rules are in effect, a special mark of some distinctive character should be applied at the stop signal. 344 GENERAL RAILWAY SIGNAL COMPANY The Committee therefore recommends: Signal Fundamentals 1. Stop. 2. Proceed with caution. 3. Proceed. Supplementary Indications to be Used Where Required. 4- Proceed at low speed. 5. Proceed at medium speed. Stop signals operated imder automatic block system rules shoula be designated by some distinctive mark to be deter- mined by each road in accordance with local requirements." Recommendations op (^ommtttee I Your Committee submits for approval the following two schemes of signaling in conformity with the .recommendations of the Committee on Transportation. Scheme No. 1 Fundamentals 1. Stop, K^ 2. Proceed with caution. 3. Proceed As means of designating stop signals operated uivier auto- matic block system rules, the following are siaggested : 1. The use of a numb^* plate, or 2. The use of a red marker light below and to the left of the active light ; or 3. The \ise of a pointed blade, the blades of other signals giving the stop indication having square ends ; or 4. A combmation of these distinguishing features. ELECTRIC INTERLOCKING HANDBOOK 345 Scheme No. 2 Supplementary Fundamentals Indications 1. Stop, ^ 2. Proceed with caution, i^ J] Proceed, Z3 4. Proceed at low speed, K> • 2. Proceed with caution, or JD ^D p 3. Proceed, or -, or 3 4. Proceed with caution on low- route, . <;> or j<;> or [<:? 5. Proceed on low-speed route, . . J3 or p or ^ 6. Proceed with caution on medium- speed route o n 7. Proceed on medium speed route. ELECTRIC INTERLOCKING HANDBOOK 347 8. Reduce to medium speed, or As means of designating stop signals operated under auto- matic block system rules, the following are suggested: 1. The use of a number plate; or 2. The use of a red marker light below and to the left of the active light ; or 3. The use of a pointed blade, the blades of other signals giving the stop indication having square ends; or 4. A combination of these distinguishing features. The above three schemes are submitted, after an earnest effort to carry out the Committee's instructions to submit a unifoiTTi scheme of signaling, with the idea that each scheme is complete in itself. SIGNAL DEFINITIONS A "non-automatic" signal is one which is in no way con- trolled by track circuit. An "automatic" signal is one, the primary control of which is the track circuit, or in other words, it is a signal which automatically gives indication in regard to the integrity of the track through its block. A "semi-automatic" signal is a manually controlled auto- matic signal and may, or may not, be interlocked. Aa to whether it is, or is not, interlocked, will be apparent from its position on the plan and its relation to other signals. It is to be understood that this manual control is direct, and that a signal is not to be considered semi-automatic because some feature of its control is dependent upon another signal which is manuallv controlled. Tne term "slotted" refers only to a mechanical signal equipped with an electric slot. A "stick semi-automatic" signal is a semi-automatic signal which will not clear automatically after it has been put to sto|) by interruption of the track circuit. It cannot be cleared again until the manually operated device controlling it has been restored normal and reversed once more. A "non-stick-automatic" signal operates automatically as long as all contacts (lever, signal, controller, etc.), other than track relay contacts affecting its control, are closed. 348 GENERAL RAILWAY SIGNAL COMPANY R. S. A. SYMBOLS FOR SIGNALS , Plate 1 (October, 1912). OmtATMC. iNtouacM Power NON- Automatic. SlotteOl (MECK.) Stick. Mow-Sroi Atrrouimc (www) a::: Special ftt«U)KO mnmna TSNOTB. tffi] Two SCNAUN& 2-PQsmoN. 0Tt)6(H)TT)7O ChuTS-OroSO n R p. B=3 A5 R 2D 2-P 0TO90 UE ft B5 Thrh PDsrrion 2-P«sfri«. Ore 45 R H R H 33 C6 P^ Z-PosfpOH. 45 TO 90 # ^ ft ^ Ke 3-Posrrum. Oto4Sto90 h! f?. f?. p„ NOTE : Arms s»40ulo alvkays be shown m normal POsrnoN . S«ciAu- 3 Position Non-Automatic, to 45 . I E24 Semi-automatic Stick , 45 to 90 . W<] Special- 3 Position Non- Automatic, Oto45. fiir Semi-AutomatiC Non- Stick , 45 to 90 . I i Absolute Stop S«6hal. j < Distant Signal. I > Permissive Stop Si6n»l. j C Train Order Signal. Enos of Blades in symbols are to be Of the actual forms used by the POAO CONCERNED. If NOT SPECIFICO THE ABOVE FORMS WILL BE USED OH PLANS. Fixed Arm. . J Upper Quadrant Sibnal. "p X"^: Lower Quadrant Si6nal. 4— ■ititi*ititititr ^1 m til J Vertcrl "I L so \ Marker 4.ights. Oiasrams of proportions for mak- LI".j ^'""''tDj IN6 SYMBOLS FOR SIGNAL BLADES , o: ELECTRIC INTERLOCKING HANDBOOK 349 R. S. A. SYMBOLS FOR SIGNALS Plate 2 (October, 1912). Groumo Mast. HS Gpouw Mast with Bracket ATiACHMeMT. Fl Offsct Bracket Post. T Bracket Post. T. SUSPENOEO Mast. Ring enclosed characteristics mean u6ht si6na1 ONLY. ? Smash Signal. Pot Signal. Home Proceed . Disc Signals. («) @ ® ® HOME Distant Distant Double Stop. Proceed. Caution. Functioned. Present Sibnal to be Removed . Present Signal to Remain. Relation of the Sishal to the Track and the Directioh of Traffic n - — ' ^ Right Hand Locations. Right Hand Si6mal . Left Hand Si6hal. Left Hand Locations. u Right Hand Signal. Left Hamo Signal. 350 GENERAL RAILWAY SIGNAL COMPANY R. S. A. LOCATION SYMBOLS Plate 3 (October, 1912). Insulating Rail Joints. Track Circuits tN Both Directions. Track Circuit on Left . None on Right. Track CtsciHT om Right, Nonc On Ltrr. Impedance Bono. Traffic Direction. Track Pan. HD Station Crossing Gate. Signal Signal Sub-Station. (uMLiss oTMf»wi»f sptcints.) Power Station . ^::::ip^^ 45 . i Tunnel. Bridge or Viaduct. Draw Bridge. NOTE: Statj wHtTMtii Otc» . Half -Tmuci Lift Bridge, Miu Post. Overhead Bridge. X Signal BfilOSE. Highway Railway Proposed Railway Crossing. Crossins. Crossing. MOTE: SPtonr nwfTKH Stiam OB EUCT»1C Rv CaOSSMiiG. o— J 9 Mail Crane. Water Tank. Water Column. Tw^ck Instrument. Torpedo Machine. Train Stops. A A A A A vI7 v-F ^ ^/ v-^ ^--MS — ^k . — f^ ^-^^ ^^f^ WfTY [j] Reuy Box. Junction Box. B B Terminal Box . Lightnin6 Arrester Box. ^^ — CAWkCiry Battery Chute . r^ nEut tot cAfActTv — pj^ Relay Box ano Post . Battery Cmute, Relay Box AND Post Combimeo . NOTE : Typc Of iHWCATOn _,^ TO Be COVEREO BY ^_ Switch Box Location . Switch Indicator . Switch Indicator ANO Switch Box. A 00 □ h n CD Cable Post With One With Two With Relay With Relay With Relay Only. Indicator. iNOtCATORS. Box. Box and One Box and Two Indicator . Indicators . ABOVE Surface . Half Above Surface. Below Surface. HiGHWAy Crossing Bell. > Battery Shelter. Tt (F16URCS indicate capacity) \^ OR Track Battery 352 GENERAL RAILWAY SIGNAL COMPANY R. S. A. LOCATION SYMBOLS Plate 5 (October, 1912). Interlocked Switches and Derails. Switch -Set nw Turn-OvtTi Switch -Set for Straight Track . Derail- Point TVpe-Deraiuhs. Derail- Point Type-non-Derailing , Derail -Uftws RAiLlYPE-DERAiLwe. Derail- Lifting RailType-Non-Dcbailino. Derail- Lifting Block Type-Nw-Oerailing. Derail- Liftwg Block Type -Derailing. NOTE: NON-mTuu)Mto smtchcs mo dcduls to k shown SAME AS ABOVE UCEPT SHA0M6 W rmAN6CES OMITTED. Runs or CONNECTIONS. Pipe-Wire (mech) . Wire Duct. Compressed Air. Pipe-Wipe and Duct. Pipe-Wire and Air. Duct and Air. Pipe -Wire, Duct Ai« [M] • Man-hou. Bolt locked Switch. S.LJyl.- Switch A Lock Movement. F.P.L.'Facmg Pomt Lock. v\/v Compensator. Arrow Indicates Direction Of MOVEMENT or Pipe Line- NORMALTO Reverse. -S ^y- OiL E»«CLOSEO Pipe Line . CRANKS. I-Way. =t1 2-WAY. I 3-Way. Interlocking or Block Statwn . BEUTIVE POSITWiOFSTAIlOII.OetMTOSAWTRACK. I/^~~M Operator Facwg Track . Operator with Back to Track. NOTE: Unless OTKCRwat specified on plan it will be assumed that where an interlocked signal is shown clear or a derail shown in non-derailins position the controlling lever is reversed. and that all other levers are normal. ELECTRIC INTERLOCKING HANDBOOK 353 R. S. A. LOCATION SYMBOLS Plate 6 (October, 1912). INTERLOCKED SWITCHES, DERAILS, ETC . 1 - SiMPLC Tutu- OUT. 2 - SIMM Cnoss-ovER . 3 - Onwi-PpiMT Ttm . 4-StHKt Slip Switch. 5 -Double Suf Switch. 6-MovABte Point Ctosswe Fi»o6. (M.P.T.) 7-SiN6ct Slip Switch kkitm M.P. F. 8 -Double Slip Switch with M.P.F. Rocking Shaft Lead-out. PIPE LINE. wme LiNt. C J wheel . « 2 3 4 6 7 8 9 CRANK Lead-out, 2-W*yCRAI»K. 4-WAt CRANK. DQEl EEE VERTICAL CRANKi. Deflecting Bar lead-out. JJJ \\\ 12 3 6 7 8 VERTICAL DEFLECTING BARS. -HORIZONTAL DEFLECTme BARS. 354 GENERAL RAILWAY SIGNAL COMPANY R. S. A. SYMBOLS FOR RELAYS. INDICATORS AND LOCKS Pi-ate 7 (October, 1912). Elcmcmts of Symbols T-T to be combined as jlj. NECESSARY . -U- X Relays, Indicators and Locks J' o d: -a- 1 TyjT , _^^ irrtl t^.j. X: OR :X: « or :X; • 1 t-tl D.C. Electro mabnet. A. C. Electro Magnet. Coil ENER6I2E0 or De-energiieo. Neutral Front Contact - Closed or Open . Neutral Back Comtact - Closed or Open . PoLAHiiEO Armature - With Contacts. 3 - Position Armature - Witn Contacts . Hi6H Current Contact. Magnetic Blow-out Contact. Bell Attachment. DooBU Winding -iPECifY if Differential. Slow Acting . OiscTVPe Indicator. OsOisc invisibu. •-Disc visible. Semaphore Type indicator, j^- 3- Position. Wire Wound Rotor .gii'Iii"" i:":i Stationary winoinb . i.'Si." High VOtTASE Wwoinb . •'—'• I 000 J' ^^3^*5 Electric lock- Show Segments for Lever in Normal Position . (SEE next page for- EXAMPLES OF COMBINATIONS.) ELECTRIC INTERLOCKING HANDBOOK. 355 R. S. A. SYMBOLS FOR RELAYS, INDICATORS AND LOCKS Plate 8 (October, 1912). h a jj. Relays , Indicators and Locks. Examples of Combinations. D.C. RELAY- Neutral- Energized - One Independent Front Contact Closed - One Independent Back Contact Open. d.c.relay-p0larized-ener6ize0- two combinatton front and back neutral contacts < LjL Two Polarized Contacts Closed - ♦ Two Polarized Contacts Open. iS M -o- -o M t t iS^ D. C. INOIGATOR - Semaphore Type- Energized - Three Front Contacts , Closed - Bell Attachment . O.C.INDICATOR- Semaphore Type -Arm Horizontal - Energized - Without Contacts . NOTE : Indicators (on ntPtATEns) without mht&cts should be showm WITH armatures to INOIUTE WHCTHER ENER64ZED OR OC-ENEB- GIZED. A. C. RELAY -One Energizing Circuit Type (S»n6le Phase) Energized - One Front Contact. A.C. RELAY- Two Energizing Circuit Type- Ener»zeo — Wire Wound Rotor - Two Neutral Front Contacts . A.C. relay-Two Energiiwc circuit type - Ehcrsizeo — Wire Wound Rotor - Two PoLARiiEO Contacts. A.C relay-Two Energizing Circuit Type- Energized - Stationary Windings — One Neutral Front Contact — Two 3- Position Contacts. D.C. interlocked RELAY. D.C. ELECTRIC BELL. OESifiNATC RESISTANCE IN OHMS OF ALL 0.C.RO-AY5, IMOlCATOHi AND LOCKS. 356 GENERAL RAILWAY SIGNAL COMPANY R. S. A. SYMBOLS FOR CIRCUIT CONTROLLER:? Plate 9 (October, 1912). CiRCurr CoMTROLLSRS Operated by Levers. Use ejther UmER System or Graphc Svstd4. tOBS wtni Exmc Be PosmoM AS NoRMM. . N-Fux Normal FosmoN OF Lever B-Nornuu.PDsmQii. D-REVEKSC kpOO-MN POSITQN. R-FuLL Reverse PoanoN. LETTHr C D R -^ 4. — ^ LEyois wiTx Mmu PosmoR as Normal. N - Normal PosmoR. L-Ru. Reverse PosmoN TO TME L^T. B-iNDlCATMM POSmOR TO THE LEFT. DHndbatmm Position to the RiOfT. R-fttJ. Reverse Posmow to the Risht. Lcrmt B N ■^ ^ -%- ^ ■^^ ■^ NOTE: H£«^ MObZORTM. UM£S MOCATE PCRTOl OF CVOE OF LEVER T>C)0u6h (tkO C-BOiT I^ CLQUO ELECTRIC INTERLOCKING HANDBOOK 357 R. S. A. SYMBOLS FOR CIRCUIT CONTROLLERS Plate 10 (October, 1912). Circuit Controllers Operated by Signals. UPPER QUADRANT. LOWER QUADRANT. ^ Closed at Only. 3 -Position ) Signals. ^ ^- ' 4 Closed at 45 Only. # --' T>. o ~Tr? ^''' ^ Closed at 90 Only. ^-* 121 Closed to 45 Closed 4-5 to 90 • t 60-70 OR 75 Signals. • 4 Closed at o Qntx. Closed in Clear Position Only. Closed. Open. ♦ --• Circuit Controller Operated by Locking Switch Circuit Controller. Mechanism of a Switch Movement. • > > Closed. Open. BR1D6E Circuit Controller. Pole Changing Circuit Controller. _J^ Spring Hang Key or Push Button. Circuit Switch. 358 GENERAL RAILWAY SIGNAL CX)MPANY R. S. A. SYMBOLS FOR CIRCUIT CONTROLLERS. RELEASES. ETC. Plate 11 (October, 1912). I/Umual Tmc PElCaSE (electric) Manual Time RclCASC . (CLECTBO-liEOWUiX.) ^ AiiTOMATc Time Release . (EUCTRIC) EMER6CNGY Release . (electric) /I OPEH. CLOSED. UTCH COMTftCt. IteACR iMSTRUMCNT CONTACT. Kmfe Swiiches. FuSW PUSN. Tin . .. Rheostat. Sonle Poa. Double Pole. Single Pole. Double Pole. SmslE Tkwow. DouBU Throw. OUCK ACTM6 CmCOIT CflNTROLLEIIS MAY BE DOTnGUiSHED BV THE LETTER '9" — ^VW — J FOEORESlSTWCe. UMlAaLE Resistumx. hiKOAftCE wrmouT Iron Core. 000000 Fuse, K=J-7 Condenser. IRON Gore ELECTRIC INTERLOCKING HANDBOOK 359 R. S A. SYMBOLS FOR BATTERIES, GENERATORS, MOTORS, ETC. Plate 12 (October, 1912). Battery. , , . + _, ,. ^ A.C.TERMINALS. d.c.terminals. Cells in Multiple. Cells in Series. ' ' Specify Type and Number of Cells . Rectifier . GlGliTv'r* looooQoJ hmmJ p = POTASH »' f 0000000] rm rm 5 = Storage '» i-secohdary. z-ooMOREseeoKOARits. EXAMPLES: I6P, IDS, ETC, TRANSFORMERS. O.C. Motor. O.C.Generator. A.C Motor. (g) (G) Motor. O.C.Generai #) (M)-(6) (|)-s NoTB. — Several readings should be made and the avera^ taken. The reaistanee ahoaki then be c(»nputed by dividing the volt&ge reading by the curreni. Hie Kmiting resisiaace used in making the test may merely be a unit of such resistanoe as to protect the instruments, it b^ng recommended, howr ever, that a variable resistance be used if available. If a voltage higher than that indicated is used, the range of the voltmeter and the re»stance unit employed will have to be increased accordingly. PULLEYS AND GEARS When it is desired to secure single reduction or increase of speed by means of belting, the speed at which each shaft should run and the diameter of one pulley being knov^Ti, multiply the diameter of the known pimey by the speed in revolutions per minute of its shaft and di\ide this product by the speed in revolutions per minute of the second shaft ; the result is the desired diameter of the second puUey. When the diameter of both pulleys and the speed of one shaft is known, multiply the speed of that shaft by the diame- to" of its pulley and divide this product by the diameter of the pulley on the other shaft; the result is the speed at which the second shaft will be run. Let D = diameter of driving pulley. d =diametar of drivai pulley. S = number of revolutions per minute of driving shaft, s =numba' of revolutions p^ minute of driven shaft. Then the above may be expressed by the following formula: , DxS a = s Where a counter-shaft is used, to obtain either size or speed of the main driving or driven pulley, calculate as above, between the known end of the transmission and the counter- shaft and then r^>eat this calculation between the counter- shaft and the unknown end. Gears in mesh transmit speeds in proportion to the nimiber of teeth they contain. Cotmt the number of teeth in the ing and substitute this quantity for the diameter of the pulleys mentioned above, in order to obtain the number cf teeth to be cut in unknown gear or speed of the second shaft. ELECTRIC INTERLOCKING HANDBOOK 373 WIDTHS OF BELTING PER HORSE POWER A rule commonly used for determining the width of belting is that "single" belt will transmit 1 H. P. for each inch in width at a speed of 1,000 feet per minute. If the speed is greater or less the power transmitted is correspondingly- increased or decreased. The rule may be stated as follows : TT p _ w X dxrpmwv • 3820 lOOO In which w= width of belt in inches. d = diameter of pulley in inches. v = velocity of belt in feet per minute. rpm= revolutions per minute. This is based on a working tension of 30 pounds per inch of width of belt. Many writers give as a safe practice for single belts in good condition a working tension of 45 pounds per inch of width, which formula gives a permissible increase in transmitted horse power of 50 per cent, over the formula „ „ w X d X rpm ^•^•="3820 For "double" belts of average thickness, the transmitting efficiency is considered as 10 to 7 compared to the single belt- ing discussed above. These formulas are based on the supposition that the arc of contact between belt and pulley is 180 degrees. For other arcs the transmitting power is approximately proportional to the ratio of the degrees of arc of contact to 180 degrees. TABLE FOR DETERMINING WIDTH OF BELTING WlI>TH OF Belt in Inches Speed in Feet per 2 3 4 5 6 HP. H.P. H. P. H.P. H. P. 500 1 1.5 2 2.6 3 1000 2 3 4 5 6 1500 3 4.5 6 7.5 9 2000 4 6 8 10 12 2500 5 7.5 10 12.5 15 3000 6 9 12 15 18 3500 7 10.5 14 17.5 21 4000 8 12 16 20 24 4500 9 13.5 18 22.5 27 5000 10 i 15 20 25 30 Note. — Based on the formula H. P. _w X d X rpm ' 3820 ' "1000 In running, the upper side of the belt should sag downward, as the belt will then be in contact with more than half the cir- 374 GENERAL RAILWAY SIGNAL COMPANY cumference of the pulley, and the power increased in the pro- portion referred to in the preceding paragraph. Best results are secured by running belt just tight enough to prevent slipping at normal load. PAINTING EXTRACTS FROM R. S. A. SPECIFICATIONS FOR ELECTRIC INTERLOCKING (1910) 800. Paint Field work. (6) Surfaces covered with rust, grease, dirt, or other foreign substances, shall be thoroughly cleaned before paint or oil is applied. (c) Paint shall not be applied to outside surfaces in freezing weather, nor to wet surfaces, nor until previous coating has thoroughly dried. (d) Finishing coats shall not be applied until after the expiration of forty-eight (48) hours after the previous coating has been applied. (e) Paints mixed on the ground shall be applied within three (3) hours after the pigment and oil are mixed. (/) Priming coats shall be applied as soon as is con- sistent with the progress of the work. (g) Second coat shall be applied in sufficient time for the thirc^ coat to be applied and dry when the installation is completed. 810. Iron Work (a) Iron work (except machine, tie plates, and iron foundation piers) not galvanized shall be painted one (1) coat of red lead and raw linseed oil and two (2) finishing coats. amount OF PAINT REQUIRED PER 1000 FEET OF trunking and capping Size of Trunking Inches Size of Capping laches Gallons (two coats) 2x 3 3x 4 4x 7 4x10 1 X 3 iViX 4 iy2x 7 2 XlO 4 9 11 Note. — The covering capacity of paint depends largely on the condition of the surface being finished, the handling of the goods by the painter; and the temperature of the surface painted. The above figures are based on average working conditions. ELECTRIC INTERLOCKING HANDBOOK 375 RAIL SECTIONS A. R A. RAILS —TYPE •• A" Weight per A B c D E F G Yard Lbs. In. In. In. In. In. m. In. 60 4% 22%4 1%6 n%4' 2^4 1%2 4 70 4% 2^ j 2%2. ii^2;2% % 4y4 80 5% 22%2- »%2 me 2V2 1 «%4 4% 90 5% 3%2 ! 1 ! 11%2; 2»A« j »A6 5V& 100 6 3% i IMe i l»/i6 ' 2% 1 %6 5V2 Fig. 278 A. R. A RAILS — TYPE "B' -^ Weight per A Yard B C D E ^ G •-^ f t ^ V ? Lb3. , In. In. In. In. In. In. in. ■n^ ' t.13- 1 60 ;4%« 70 48^k 80 i 41^ « 2^i« % 12%4 11%9 2% 2% 97/4 „ «y64 «^'«4 31^6 4%4 4%6 4*%4 r "^^ o 90 ' 5iy»4' 2% 1 1%2 100 : 5*^64 2B%4' 1%4 1 *?S2 -/xo 18%*! 2%6 L G -< 1*^^ 22i,4o' »/4« Fig. 279 A. S. C. E . RAILS Weight per Yard A B c D £ F k-eH Lbs. in. In. 21^^ 21%4 2% 21%2 2»6/«4 2«^ 2% 255/e4! 2«%4J 3%4 1 3i%2; In. In. In. In. In. 55 60 65 70 75 80 85 90 95 100 110 4%6 4% 4Ti6- 4% 41%6 5 5%6 5% 5»A6 5% 6% 2%2 *%4 2%2 2%2 11^64 2^ 1%2 1 2% 1%2 21%2 ll%2j 2%« 12y64! 21%2 1V„ 1 9V„ 8Ve4 "/32 «5/«4 »4« 4^6 4y4 4% 4i%fl 5 5^6 •s^ o \ [ F \ 1 n "" , A 57/6^1 135/^4' 2«A6 [. G F J "/64 5% 5%« 5% 6% iG. 280 "^64 8^2 1 l^"/^2 1*^64 145/64 12%2 21^6 2% 2^/8 376 GENERAL RAILWAY SIGNAL COMPANY TABLE OF TURNOUTS FROM STRAIGHT TRACK Gauge, 4 Feet, 8^^ Inches. Throw of Switch, 5 Inches Fig. 281 Lead-Dist. Frog Num- ber Frog Angle FPE Length Point of Frog to Toe PD Length Point of Frog to Heel PE Length of Switch Rail AC Switch Angle BAC = TOC Radius of Center Line OC-iga Degree of Lead Curve Actual Point of Switch Rail to Actual Point of Frog AB III £ 5 £ 5 £d ill £ II 1 6 9-31-38 4- 7- 11-0 2-36-19 265.39 21-43-04 47.98 7 8-10-16 4- 5 8- 1 16-6 1-44-11 362.08 15-52-29 62.10 8 7-09-10 4- 9 8- 9 16-6 1-44-11 487.48 11-46-27 67.98 9 6-21-35 6- 10- 16-6 1-44-11 605.18 9-28-42 72.28 9V2 6-01-32 6- 10- 16-6 1-44-11 695.45 8-14-45 75.71 10 5-43-29 6- 10- 6 16-6 1-44-11 790.25 7-15-18 77.93 11 5-12-18 6- 11- 6 22-0 1-18- 8 922.65 6-12-47 94.31 12 4-46-19 6- 5 12- 1 22-0 1-18- 8 1098.73 5-12-59 100.80 15 3-49-06 7- 8 14-10 33-0 0-52- 5 1744.38 3-17-01 133.28 16 3-34-47 8- 16- 33-0 0-52- 5 1993.24 2-52-59 137.57 18 3-10-56 8-10 17- 8 33-0 0-52- 5'2546.31 2-14-31 146.51 20 2-51-51 9- 8 19- 4 33-0 0-52- 53257.26 1-45-32 157.42 24 2-23-13 11- 4 23- 2 33-0 0-52- 54886.16 1-10-21 177.22 Above from table by American Railway Engineering Association. ELECTRIC INTERLOCKING HANDBOOK 377 TABLE OF CROSSOVERS Gauge, 4 Fekt, 8% Inches. Throw op Switch, 5 Inches Fig. 282 Frog Number Lead Distance (A) between Frog Points for Track 1 Centers Below 11' 12' 13' 14' 16' 16' 1 Feet Feet Feet 1 Feet Feet Feet Feet 6 47.98 9.5 15.5 21.5 27.5 33.5 39.5 7 62.10 11.1 18.1 25.1 32.1 39.1 46.1 8 67.98 12.7 20.7 28.7 36.7 44.7 52.7 9 1 72.28 14.2 23.2 32.2 41.2 50.2 59.2 9^2 75.71 15.0 24.5 34.0 43.5 63.0 62.5 10 77.93 15.8 25.8 35.8 45.8 65.8 65.8 11 94.31 17.4 28.4 39.4 50.4 61.4 72.4 12 100.80 19.0 31.0 43.0 65.0 67.0 79.0 15 133.28 23.8 38.8 53.8 68.8 83.8 98.8 16 137.57 25.3 41.3 57.3 73.3 89.3 105.3 18 146.51 28.4 46.4 64.4 82.4 100.4 118.4 20 157.42 31.6 51.6 71.6 91.6 111.6 131.6 24 177.22 38.0 62.0 ' 86.0 110.0 134.0 158.0 Frog Number TOTAL Length of Crossover for Track Centers Below | 11' 12' 13' 14' 15' 16' Feet Feet Feet Feet Feet Feet » 105.5 111.5 117.5 123.5 129.5 135.5 7 1 135.3 142.3 149.3 156.3 163.3 170.3 8 148.7 j 156.7 164.7 i 172.7 180.7 188.7 9 158.8 ! 167.8 176.8 j 185.8 194.8 203.8 9^ 166.4 j 175.9 185.4 ! 194.9 204.4 213.9 10 171.7 1 181.7 191.7 1 201.7 211.7 221.7 11 206.0 217.0 228.0 239.0 250.0 261.0 12 220.6 232.6 244.6 i 256.6 268.6 280.6 15 290.4 305.4 320.4 335.4 350.4 365.4 16 1 300.4 316.4 332.4 348.4 364.4 380.4 18 321.4 339.4 357.4 375.4 393.4 411.4 20 346.4 366.4 1 386.4 406.4 426.4 446.4 24 392.4 416.4 440.4 464.4 488.4 512.4 Note. — Distance (A) between frog points based on formula Distance = (track centers — 2 x gauge) x frog number. 378 GENERAL RAILWAY SIGNAL COMPANY Per Track ^ c 5.fc BOND WIRES AND CHANNEL PINS Diagram below gives the actual number of bond wires and channel pins required for bonding single track road (2 rails) for distances up to 6,000 feet. To this should be added 25 bond wires and 50 channel pins for each switch, and to the total 5 per cent, added to cover loss. 825 1500 750 1350 675 lEOO 600 »050 525 900 il50 Per Tra cK Is. |g. 704 W08 :==, 640 IZ80 1000 2000 3000 4000 5000 6000 ft of Track saso Fig. 283 ELECTRIC INTERLOCKING HANDBOOK 379 TWIST DRILL AND 3TEEL WIRE GAUGE Xo. Size Inch .0. Size No. Size No. Size No. Size Inch Inch Inch Inch 1 .2280 13 .1850 25 .1495 37 .1040 49 .0730 2 .2210 14 .1820 26 .1470 38 .1015 50 .0700 3 .2130 15 .1800 27 .1440 39 .0995 51 .0670 4 .2090 16 .1770 28 . 1405 40 .0980 52 .0635 5 .2055 17 .1730 29 .1360 41 .0960 53 .0595 6 .2040 18 .1695 30 .1285 42 .0935 54 .0550 .2010 19 .1660 31 .1200 43 .0890 55 .0520 8 .1990 20 .1610 32 .1160 44 .0860 56 .0465 9 .1960 «>1 .1590 33 .1130 45 .0820 57 .0430 10 .1935 22 .1570 34 .1110 46 .0810 58 .0420 11 .1910 23 .1540 35 .1100 47 .0785 59 .0410 12 . 1890 24 .1520 36 .1065 48 .0760 60 .0400 Reprinted by permission from Kent's "Mechanical Engineers' Pocket Book. STUBS' STEEL W^RE GAUGE Size Size Size Size Siz3 No. - No. No. No. Z 1 Inch 413 Inch Inch Inch Inch D .246 19 .164 41 .095 63 030 Y 404 C .242 20 .161 42 .092 64 035 X 397 B .238 21 .157 43 .088 65 033 w 386 A .234 22 .155 44 .085 66 032 V 377 1 .227 23 .153 45 .081 67 031 u 368 2 .219 24 .151 46 .079 68 030 T 358 3 .212 25 .148 47 .077 69 029 s 348 4 .207 26 .146 48 .075 70 027 R 339 5 .204 27 .143 49 .072 71 026 Q 332 6 .201 28 .139 50 .069 72 024 p 323 7 .199 29 .134 51 .066 73 023 316 8 .197 30 .127 52 .063 74 022 N 302 9 .194 31 .120 53 .058 75 020 M 295 10 .191 32 .115 54 .055 76 018 L 290 11 .188 33 .112 55 .050 77 016 K 281 12 .185 34 .110 56 .045 78 015 J 277 13 .182 35 .108 57 .042 79 014 I 272 14 .180 36 .106 58 .041 80 013 H 266 15 .178 37 .103 59 .040 G i 261 16 .175 38 .101 60 .039 F 257 17 .172 39 .099 61 .038 E 250 18 .168 40 .097 62 .037 The Stubs' Steel Wire Gauge is used in measuring drawn steel wire or drill rods of Stubs' make, and is also used by many makers of American drill rods. Reprinted by permission from Kent's "Mechanical Engineers' Pocket Book." 380 GENERAL RAILWAY SIGNAL COMPANY STANDARD SCREW THREADS. NUTS, BOLT AND LAG HEADS U. S. STANDARD Inch %« % %a % %« % % % 1 1% 1V4 1% 1% 1% 1% 1% 2 2% 2% 2% 3 3^4 3% 3% 4 4% 4% 4% 5 5% 5^ 5% J Inside , Threads Diam. of Width of Outside \ Diam. j Diago- j Height per Inch Core Fiat | Diam. ' Hex or > nal Sq. of Head {Hex. Head Sq.Head Head Inch I Inch Inch | Inch 20 18 16 14 13 12 11 10 9 8 7 7 6 6 5% 5 5 4% 4% 4 4 3H 3% 3% 3 3 2% 2% 2% 2% 2% 2% 2% 2Vi .185 .240 .294 .344 .400 .454 .507 .620 .731 .837 .940 1.065 1.160 1.284 1.389 1.490 1.615 1 712 1.962 2.175 2.425 2.628 2.878 3.100 3.317 3.566 3.798 4.027 4.255 4.480 4.730 4.953 5.203 5.423 .0096 .0104 .0113 .0125 .0140 .0156 .0180 .0180 .0210 .0210 .0227 .0250 .0250 .0280 .0310 .0310 .0357 .0357 .0384 .0410 .0410 .0435 .0460 .0480 .0500 .0500 .0526 .0526 .0555 %6 !%• *%9 1 1%* 1%2 1%« 1*^2 1% 2^82 2%« 2% 2% 2i%er Inch Ins. Ins. Ins. Ft. Sq. In. Lb?. No. V4 .540 .088 7.075 .104 .42 18 % .675 .091 5.658 .191 .56 18 ¥2 .840 .109 4.547 .304 .84 14 % 1.050 .113 3.638 .533 1.12 14 1 1.315 .134 2 904 .861 1.67 iiy2 iy4 1.660 .140 2.301 1.496 2.24 im IVo 1.900 .145 2.010 2.036 2.68 iiy2 2 2.375 .154 1.608 3.356 3.61 11% 2¥2 2.875 .204 1.329 4.780 5.74 8 3 3.500 .217 1.091 7.383 7.54 8 3y2 4.000 .226 .955 9.887 9.00 8 4 4.500 .237 .849 12.730 10.66 8 4y2 5.000 .246 .764 15.961 12.34 8 5 5.563 .259 .687 19.986 14.50 8 6 6.625 .280 .577 28.890 18.76 8 7 7.625 .301 .501 38.738 23.27 8 8 8.625 .322 .443 50.027 28.18 8 9 9.625 .344 .397 62.730 33.70 8 10 10.75 .366 .355 78.823 40.06 8 382 GENERAL RAILWAY SIGNAL COMPANY SQUARE HEAD LAG SCREWS Diameter in Inches ¥l6 % Tie V2 %6 5/^ %, Vs 1 Length in Inches Average Weight per Hundred | Lbs. Lbs. Lbs. Lbs. Lbs. Lbs. Lbs Lbs. Lbs. iy2 4.2 6.5 - 9.2 13.0 1% 2 4.7 5.2 7.1 7.7 10.0 10.9 13.8 14.9 23.0 24.8 ly^ 5.7 8.4 11.8 16.1 24.5 27.3 .... 2^2 6.2 9.2 12.7 17.4 26.0 29.0 43.0 3 7.2 10.6 14.6 19.0 29.2 32.9 48.3 75.0 3^2 8.2 12.0 16 6 21.5 32.5 36.9 53.8 78,5 90 4 9.2 13.5 18.8 24.0 35.9 41.0 59.6 82.0 99 4^2 10 2 15.0 20.7 26.5 39.3 44.9 65.5 88.0 108 5 11,3 16.5 22.8 29.0 42.7 48.8 71.5 90.0 118 hVi 12.4 18.0 24.9- 31.5 46.1 52.7 77.5 98.0 128 G 13.5 19.5 27 34.0 49.5 56.6 83.5 106.0 138 Note. — For dimensions of lag screw heads, see page 380. COMMON WIRE NAILS Size Length in Inches Diameter in Inches Approx. Number to Lb. Approx. Lbs. per 1000 2D 1 .072 876 1 14 3D IVi .080 568 1 76 4D l»/2 .100 316 3.16 5D 1% .100 271 3.69 6D 2 .113 181 5.53 7D 2y4 .113 161 • 6.21 8D 2V2 .131 106 9.43 9D 2% .131 96 10.4 19D 3 .148 69 14.5 12D 3y. .148 63 15.9 16D 3^2 .162 49 20.4 20D 4 .192 31 32.3 30D 4^2 .207 24 41.7 40D 5 .225 18 55.6 50D 5^2 .244 14 71.4 60D 6 .263 11 90.9 ELECTRIC INTERLOCKING HANDBOOK 383 TABLE OF BOARD MEASURE Size Length in Feet 10 12 14 16 18 Feet Board Measure 1x2 1% 2 2y3 2% 3 1x4 3Vs 4 4% 5% 6 1x6 5 6 -7 8 9 1x8 6% 8 9Vs 10% 12 1x10 8V3 10 11% 13% 15 1 X 12 1(5 12 14 16 18 1 X 14 11% 14 16% 18% 21 2x4 6% 8 9V3 10% 12 2x6 10 12 14 16 18 2x8 13% 16 18% 21% 24 2x10 16% 20 23% 26% 30 2x12 20 24 28 32 36 2 X 14 23V3 28 32% 37% 42 3x8 20 24 28 32 36 3x10 25 30 35 40 45 3x12 30 36 42 48 54 3x14 35 42 49 56 63 4x4 13V3 16 18% 21% 24 4x6 20 24 28 32 36 4x8 23% 32 37% 42% 48 4x10 33^3 40 46% 53% 60 4x12 40 48 56 64 72 4x 14 46% 56 65% 74% 84 Note. — Ivength in teetX width in feet X thickness in inches: of feet board measure. (1 cu. ft. of lumber=12 board feet.) number 384 GENER.4L RAILWAY SIGNAL COMPANY BAUxMfi'S HYDROMETER AND SPECIFIC GRAVITIES COMPARED Degrees Baume Liquids Heavier than Water. Sp. Gr. Liquids Lighter than Water, Sp. Gr. Degrees Baume Liquids Heavier than Water. Sp. Gr. Liquids Lighter than Water, Sp. Gr. 0.0 1.000 28.0 1.239 0.886 1.0 1.007 29.0 1.250 0.881 2.0 1.014 30.0 1.261 0.875 3.0 1.021 31.0 1.272 0.870 4.0 1.028 32.0 1.283 0.864 5.0 1.036 33.0 1.295 0.859 6.0 1.043 34.0 1.306 0.854 7.0 1.051 35.0 1.318 0.849 8.0 1.058 36.0 1.330 0.843 9.0 1.066 37.0 1.343 0.838 10.0 1.074 1.000 38.0 1.355 0.833 11.0 1.082 0.993 39.0 1.368 0.828 12.0 1.090 0.986 40.0 1.381 0.824 13.0 1.099 0.979 41.0 1.394 0.819 14.0 1.107 0.972 42.0 1.408 0.814 15.0 1.115 0.966 44.0 1.436 0.805 16.0 1.124 0.959 46.0 1.465 0.796 17.0 1.133 0.952 48.0 1.495 0.787 18.0 1.142 0.946 50.0 1.526 0.778 19.0 1.151 0.940 52.0 1.559 0.769 20.0 1.160 0.933 54.0 1.593 0.761 21.0 1.169 0.927 56.0 1.629 0.753 22.0 1.179 0.921, 58.0 1.667 0.745 23.0 1.189 0.915 60.0 1.706 0.737 24.0 1.198 0.909 65.0 1.813 0.718 25.0 1.208 0.903 70.0 1.933 0.700 26.0 1.219 0.897 75.0 2.071 0.683 27.0 1.229 0.892 Reprinted by permission from "Kent's Mechanical Engineers' Pocket Book. ELECTRIC INTERLOCKING HANDBOOK 385 SPECIFIC GRAVITY OF LIQUIDS AT 60 DEGREES FAHR. . 1.203 Oil, Olive, . . . . .0.92 .\cid. Nitric, . 1.217 Oil, Palm, . . . . . 0.97 Acid, Sulphuric, .... .\lcohol, pure, .Vlcohol, 95 per cent., . .\lcohol, 50 per cent., .\mmonia, 27 .9 per cent.. Bromide, . 1.849 . 0.794 . 0.816 . 0.934 . 0.891 . 2.97 Oil, Petroleum, . Oil, Rape, . . . Oil, Turpentine, . Oil, Whale, . . . . 0.78 to 0.88 . . 0.92 . . 0.87 . .0.92 Tar, . . 1. Vinegar, . . . . Water Water, Sea, . . . .1.08 . . 1. . . 1.026 to 1.03 Carbon, disulphide, . . Ether, Sulphuric, . . . Oil, Lin.seed . 1.26 .. 0.72 . 0.94 Reprinted by permission from "Kent's Mechanical Engineers' Pocket Book." SPECIFIC GRAVITY AND WEIGHT OF WOOD Specific Gravity ^6 Specific Gravity If. Avge. Avge. Alder, .... 0.56 to 0.80 0.68 42 Hornbeam, 0.76 0.76 47 Apple 0.73 to 0.79 0.76 47 Juniper, . . 0.56 0.56 35 Ash, .... 0.60 to 0.84 0.72 45 22 Larch, . . . Lignum vitae 0.56 0.56i 35 1 Bamboo, . . 0.31 too. 40 0.35 0.65 to 1.33-1.00 62 Beech, . . 0.62 to 85 73 46 41 Linden, . . Locust, . 0.604 0.728 37 46 Birch 0.56 to 0.74 0.65 Box, .... 0.91 to 1.33 1.12 70 Mahogany, . 0.56 to 1.06 0. 81 1 51 Cedar, .... 0.49 to 0.75 0.62 39 Maple, . . . 0.57 to 0.79 0.68: 42 Cherry, . . . 0.61 to 0.72 0.66 41 Mulberry, . 0.56to0.90 0.73i 46 Chestnut, . . C.46 to 0.66 0.66 35 Oak, Live, . 0.96 to 1.26 1.11 69 Cork, .... 0.24 24 15 Oak, White, 0.69 toO. 86 0.77 48 Cypress, . . 0.41 toO.66 0.53 33 Oak, Red, . 0.73 to 0.75 0.74 46 Dogwood, . . 0.76 0.76 47 Pine, White, 0.35 to 0.55 0.45 28 Ebony, . . . 1 13 to 1 33 1 23 76 38 Pine,Yellow, Poplar, . . 0.46 to 0.760.61 0.38 to 0.58 0.48 38 30 Elm 0.55 to 0.78 0.01 Fir, . 48 to 70 59 37 Spruce, . . Sycamore, . 40 to 50 45' 28 Gum, .... 84 to 1.00 0.92 57 0.59 to 0.62 0.60 37 Hackmatack, . 59 0.59 37 Teak, . . . 0.66 to 0.98 0.821 51 Hemlock, . . 0.36 to 0.41 0.38 24 Walnut, . . 0.50 to 0,67 0.58: 36 Hickory, . . . 0.69to0 94 0.?7 48 Willow, . . 0.49 to 0.59 0.54 34 Holly 0.76 0.76 47 Reprinted by permission from "Kent's Mechanical Engineers' Pocket Book." 386 GENERAL RAILWAY SIGNAL COMPANY SPECIFIC GRAVITY AND WEIGHT OF STONES, BRICK, CEMENT. ETC. (Pure Waters 1.00.) Sp. Gr. Lb. per Cu. F 1.39 87 1.6 100 1.79 112 2.0 125 2.16 135 2.24 to 2.4 140 to 150 2.18 136 1.6 100 1.79 112 2.8 to 3.2 3.05 to 3.15 92 115 1.92 to 2. 4 120 to 150 1.92 to 2. 48 120 to 155 1.15 to 1.28 72 to 80 1.44 to 1.76 90 to 110 4. 250 2.5 to 2.75 156 to 172 2.88to3.14 180 to 196 2.56 to 2.72 160 to 170 1.6 to 1.92 100 to 120 2.08 to 2.4 130 to 150 3.2 to 3.52 200 to 220 0.88 to 0.92 55 to 57 0.8 to 0.96 50 to 60 2.30 to 2.90 140 to 185 2.4 150 2.56 to 2.88 160 to 180 2.24 to 2.56 140 to 160 2.24 to 2. 88 140 to 180 2.80 175 1.44 to 1.6 90 to 100 1.67 to 1.92 104 to 120 1.15 72 1.50 to 1.81 93 to 113 2.64 165 1.44 to 1.76 90 to 110 1.89 to 2. 07 118 to 129 2.24 to 2.4 140 to 150 2.72 to 2.88 170 to 180 2.65 to 2. 8 166 to 175 2.16 to 3.4 135 to 200 2.72 to 3.4 170 to 200 1.76 to 1.92 110 to 120 Asphaltum, Brick. Soft Brick, Common Brick, Hard, . Brick, Pressed, Brick, Fire, Brick, Sand-lime Brickwork in mortar, . . . . Brickwork in cement, . . . . Cement, American, natural, . Cement, Portland Cement, Portland, loose, . . Cement, Portland, in barrels. Clay Concrete, Earth, loose, Earth, rammed, Emery, Glass Glass, flint Granite Gravel Gypsum, Hornblende, .... Ice, Lime, quick, in bulk. Limestone Magnesia, Carbonate, Marble, Masonry, dry rubble. Masonry, dressed, . Mica, Mortar, Mud, soft flowing, . Pitch Plaster of Paris, . . Quartz Sand, Sand, wet, Sandstone Slate, Soapstone, .... Stone, various, . . . Trap, TUe. ....... Reprinted by permission from Kent's " Meclianical Engineers' Pocket Book." ELECTRIC INTERLOCKING HANDBOOK 387 SPECIFIC GRAVITY AND WEIGHT OF METALS Specific Grav- Weight 1 Weight Specific Gravity. ity. Approx per per Range According Mean Value, Cubic Cubic to Several Authorities used in Calculation of Weight Foot Inch Lbs. Lba. Aluminum 2.56 to 2.71 2.67 166.5 0.0963 Antimony, 6.66 to 6.83 6.76 421.6 0.2439 Bismuth, 9.74 to 9.93 9.82 612.4 0.3544 Brass: Copper + Zinc 80 20 ] r8.60 j 8.40 8.36 536.3 0.3103 70 30 7.8 to 8.6 523.8 0.3031 60 40 j 521.3 0.3017 50 50 j t8.20 511.4 0.2959 ( Cop., 95 to 80 / Bronze ^ _,. c x on i ( Tm, 5 to 20 > 8.52 to 8.93 8.853 552. 0.3195 Cadmium, 8.6 to 8.7 8.65 539. 0.3121 Calcium, 1.58 1.58 98.5 0.0570 Chromium, 5.0 5 311.8 0.1804 Cobalt, 8.5 to 8.0 8.55 533.1 0.3085 Gold, purs 19.245 to 19.331 19.258 1200.9 .6949 Copper, 8.69 to 8.92 8.853 552. 0.3195 Iridium, 22.88 to 23. 22.38 1398. 0.8076 Iron, Ca^t, 6.85 to 7.48 7.218 450. 0.2604 Iron, Wrought, . . . 7.4 to 7.9 • 7.70 489. 0.2779 Lead, ....... 11.07 to 11.44 11.38 709.7 0.4106 Manganese 7. to 8. 8. 499. 0.2887 Magnesium, 1.69 to 1.75 1.75 109. 0.0841 f 32° 13.60 to 13.62 13.62 849 3 0.4615 Mercury. ... -^ 60" 13.58 13.58 843.8 0.4900 (212° 13.37 to 13 38 13.38 834.4 0.4828 N'ickel, 8.279 to 8.93 8.8 548.7 0.3175 Platinum 20.33 to 22.07 21.5 1347.0 0.7758 Potassium 0.865 0.865 53 9 |0.0312| Silver 10.474 to 10.511 10.505 655.1 0.3791 Sodium 0.97 0.97 69.5 0.0350 Steel 7.69* to 7.93'>t 7.854 489.6 0.2834 Tin, 7.291 to 7.409 7.350 458.3 0.2652 Titanium, 5.3 5.3 330 5 0.1913 Tungsten, 17. to 17.6 17.3 1078.7 0.6243 Zinc, 6.86 to 7.20 7.00 436.5 0.2528 * Hard and burned. t Very pure and soft. The sp. gr. decreases as the carbon is increased. In the first column of figures the lowest are usually those of cast metals, which are more or less porous; the highest are of metals finely rolled or drawn into wire. Reprinted by permission /Tom "Kent's Mechanical Engineers' Pocket Book." 388 GENERAL RAILWAY SIGNAL COMPANY TABLES OF WEIGHTS AND MEASURES Linear Measure 12 inches (in.), .... =1 foot (ft.) 3 feet, =1 yard (yd.) 5.5 yards, =1 rod (rd.) 40 rods, =1 furlong (fur.) 8 furlongs, -=1 mile (mi.) 1 mi. = 8 fur. =320 rods = 1760 yd. = 5280 ft. = 63,360 in. Square Measure 144 square inches (sq. in.), =1 square foot (sq. ft.) 9 square feet, .... =1 square yard (sq. yd.) 301A square yards,. ... =1 square rod (sq. rd.) 160 square rods, . . . . = 1 acre (A) 640 acres, =1 square mile (sq. mi.) 1 sq. mi. = 640 acres = 102.400 sq. rd. = 3,097,600 sq. yd. = 27,878,400 sq. ft. =4,014,489,600 sq. in. Cubic Measure 1,728 cubic inches (cu. in.), = 1 cubic foot (cu. ft.) 27 cubic feet, =1 cubic yard (cu. yd.) 128 cubic feet, =1 cord (cd.) 24% cubic feet, =1 perch (P.) 1 cu. yd. =27 cu. ft. =46,656 cu. in. Measures of Angles or Arcs 60 seconds ("), .... =1 minute (0 60 minutes, =1 degree (°) 90 degrees, =1 right angle or quadrant ( d ) 360 degrees, . . . . =1 circle (cir.) 1 cir.=360° = 21,600' = l,296,000". Avoirdupois Weight 437.5 grains (gr.), .... =1 ounce (oz.) 16 ounces, =1 pound (lb.) 100 pounds =1 hundredweight (cwt.) 20 cwt. or 2,000 lb., . . =1 ton (T.) 1 T.=20 cwt. =2,000 lb. =32.000 oz. = 14.000,000 gr. The avoirdupois pound contains 7,000 grains. Dry Measure, 2 pints (pt.), =1 quart (qt.) 8 quarts, =1 peck (pk.) 4 pecks, =1 bushel (bu.) 1 bu.=4 pk. = 32 qt. = 64 pt. The U. S. struck bushel contains 2,150.42 cubic inches = 1.2444 cubic feet. By law, its dimensions are those of a cylinder 18y2 inches in diameter and 8 inches deep. The ELECTRIC INTERLOCKING HANDBOOK 389 heaped bushel is equal to VA struck bushels, the cone being six inches high. The dry gallon contains 268.8 cubic inches, being Vh of a struck bushel. For approximations, the bushel may be taken at 1^ cubic feet, or a cubic foot may be considered % of a bushel. The British bushel contains 2,218.19 cubic inches = 1.2837 cubic feet = 1.032 U. S. bushels. Liquid Measure 4 gills (gi.), =lpint (pt.) 2 pints, -. =1 quart (qt.) 4 quarts, =1 gallon (gal.) 3IV2 gallons, =1 barrel (bbl.) 2 barrels, =1 hogshead (hhd.) 1 hhd.- = 2 bbl. =63 gal. =252 qt. = 504 pt. =2,016 gi. The U. S. gallon contains 231 cubic inches = .134 cubic feet approximate ; or 1 cubic foot contains 7.481 gallons. The fol- lowing cylinders contain the given measures very closely : Diam. Height Diam. Height Gill, ..... 1% in. 3 in. Pint, 3y2 in. 3 in. Quart, .... 3^2 in. 6 in. When water is at its maximum density, 1 cubic foot weighs 62.425 pounds and 1 gallon weighs 8.345 pounds. For approximations, 1 cubic foot of water is considered equal to 1V2 gallons and 1 gallon as weighing SVs pounds. The British Imperial gallon, both liquid and dry, contains 277.274 cubic inches =.16046 cubic feet, and is equivalent to the volume of 10 pounds of pure water at 62 degrees Fahr. To reduce British to U. S. liquid gallons, multiply by 1.2. Con- versely, to convert U. S. into British liquid gallons, divide by 1.2 ; or, increase the number of gallons %. Miscellaneous Table 12 articles, =1 dozen. 12 dozen, =1 gross. 12 gross, =1 great 2 articles, =1 pair. 20 articles, =1 scoref. 24 sheets, =1 quire. 20 quires, =1 ream. Gallon, . . 7 in. 6 in. 8 gallons. . 14 in. 12 in. 10 gallons. . 14 in. 15 in. 390 GENERAL RAILWAY SIGNAL COMPANY- FRENCH OR METRIC MEASURE The metric unit of length is the metre = 39.37 inches. The metric unit of weight is the gram = 15.432 grains. The following prefixes are used for subdivisions and multi- ples: Milli = 1/1000, Centi = 1/100, Deci = l/iO, Deca = 10, Hecto = 100, Kilo = 1000, Myria = 10,000. FRENCH EQUIVALENTS OF AMERICAN AND BRITISH MEASURE Measures of Length French British and U. S. (39.37 inches 1 metre, = or 3.28083 feet ( or 1.09361 yards .3048 metre, =1 foot 1 centimetre =.3937 inch 2.54 centimetres, =1 inch 1 ,v,;ii;rv,«<^« i .03937 inch, or 1 millimetre, =] y^^ ^^^ ^^^jy 25.4 millimetres, =1 inch 1 , -I ^^„ 5 1093.61 yards or 1 kilometre, = 1 0.62137 mile Measures of Surface French British and U. S. - . S 10.764 square feet 1 square metre, =\ 1.196 square yards .836 square metre, =1 square yard .0929 square metre, =1 square foot 1 square centimetre =.155 square inch. 6,452 square centimetres, . . . . = 1 square inch - .,v ^ ( .00155 square inch 1 square miUimetre, ={ 1973.5 ch-cular mils. 645.2 square millimetres =1 square inch 1 centiare = l square metre,. . =10.764 square feet 1 are = l square decametre, . . =1076.41 square feet - , ^ -rt^ ( 107641 square feet 1 hectare = 100 ares, = j 2.4711 acres , ., ^ f .386109 square mile 1 square kilometre, ^ \ 247.11 acres 1 square myriametre, .... =38.6109 square miles Reprinted by permission from " Kent's Mechanical Engineer's Pocket Book." electric lnterlccking handbook 39l Measures of Volume French British and U. S. 1 cubic metre, 35.314 cubic fee*. 1.308 cubic yards .7645 cubic metre, . =1 cubic yard .02832 cubic metre, . = 1 cubic foot 1 ^„k;^ ^^«;»v,^f^« J 61.023 cubic inches 1 cubic decimetre, ^ ] .0353 cubic foot 28.32 cubic decimetres =1 cubic foot 1 cubic centimetre =.061 cubic inch 16.387 cubic centimetres, . .... =1 cubic inch 1 cubic centimetre = 1 miliilitre, =.061 cubic inch 1 centilitre,. ........ = .610 cubic inch 1 decilitre, . .' =6.102 cubic inches intre^l cubic decimetre.. . = | Kltuarlra S, 1 hectolitre or deeistere. . . . ^ IItS busiTeirU. S. 1 stere, Icilolitre, or cubic metre, = { If^^^ ^^,^^'^'s. Measures of Capacity French British and U. S. r 61.023 cubic inches I .03531 cubic foot 1 litre (1 cubic decimetre), . . = { .2642 gallon (Am.) I 2.202 pounds of L water at 62° Fahr. 28.317 litres, =1 cubic foot 4.543 litres, =1 gallon (British) 3.785 litres, =1 gallon (American) Measures of Weight French British and U. S. 1 gramme, =15.432 grains .0648 gramme, =1 grain 28.35 grammes, = 1 ounce avoirdupois 1 kilogramme, =2.2046 pounds .4536 kilogramme, =1 pound r.9842 ton of 2,240 1 tonne or metric ton, 1 pounds •1,000 kilogrammes, =1 19.68 cwts. [2204.6 pounds 1.016 metric tons, - = [1 ton of 2,240 1,016 kilogrammes, = i" pounds Reprinted by permUaion from "Kfvfx Mechanical Engineers' Pocket Book. 392 GENERAL RAILWAY SIGNAL COMPANY TEMPERATURES, FAHRENHEIT AND CENTIGRADE F. C. jj F. 1 C. F. 1 C. jj F. j C. F. 1 C. 11 F. C. J! F. 1 C. -4( )-40. '1^^ -3.3 92:33.3 t 158 70. 224 !l06.7 290 143.3 360 1182.2 — 3( )— 39.^ I! 27 —2.8 93 33.9 1 159 70.6 225 |107.2 291 143.9 370 |187 8 — 3J 5-38.< ) 28 —2.2 94 34.4 160 71.1 226 107.8 292 144.4 380 I193.3 —3' — 38.C {, 29 —1.7 95 35. 161 71.7 227 108.3 293 145. 390 198.9 — 3( )— 37.J I 30 — l.I 96 35.6 162 72.2 228 108.9 294 145.6 400 204 4 — 3^ —37.^ 1 31 —0.6 97 36.1 163 72.8 229 109.4 295 146.1 410 i210. — 3-^ -36./ i 32 0. 98 36.7 164 73.3 230 110. i! 296 146.7 420 215.6 —33'— 3b. J 1 33 +0.6 99 37.2 165 73.9 231 110.6 297 147.2 430 ,221 1 — 32|— 35.f 1 34 1.1 100 37.8 166 74.4 232 111.1:1 298 147.8 440 !226.7 -31-35. 35 1.7 10138.3 167 75. 233 111.7|i 299 148.3 450 232 2 —30-34.4, 36 2.2 102 38.9 168 75.6 234 112.2 300 1148.9 460 237 8 1 -29|-33.9 37 2.8 103 39.4 169 76.1 235 112.81 301 149.4 470 243.3 — 28!— 33.3'l 38 3.3 104 40. 170 76.7 236 113.3 1 302 150. 480 248.9 —27 -32. 8: 1 39 3.9 105 40.6 171 77.2 237 113.9 303 150.6 490 254 4 ~l%~ll'^\ ^0 4.4 106 41.1 172 77.8 238 114.4 304 151.1 500 260. -25-31.7 41 5. 107 41.7 173 78.3 239! 115. ij 305 151.7 510 :265.6 —24: -31.1 42 5.€ 108142.2 174 78.9 2401115.6 306 152.2 520 271 1 -23-30.6 43 6.1 109 42.8 175 79.4 241 116.1 1 307 152.8 530 276 7 —22 1-30. II 44 6.7 110 43.3 176 80. 242 116. 7;j 308 153.3 540 282.2 — 211— 29.4:j 45 7.2 111 43.9 177 80.6 243 117. 2J 309 153.9 550 287 8 —20—28.9 ■" 46 7.8 112 44.4 178 81.1 244 117.8! 310 154.4 560 293.3 -19 "" " —28.3 \fo 8.3 113 45. 179 81.7 245!ll8.3! 311 155. 1 570 298.9 —18 —27.8 \m 8.9 114 45.6 180 82.2 246 118. 9! 312 155.6 580 304 4 —17 -27.2 49 9.4 115 46.1 181 82.8 247 119.4: 313 156.1 590 310. —16 —26.7 50 10. 116 46.7 182 83.3 248 120. j 314 156.7 600 315 fi —15 —26.1 51 10.6 117 47.2 183 83.9 249 120.6; 315 1157.2 610 321 1 —14 -25.6 ^l 11.1 118 47.8 184 84.4 250 121.11 316 1I57.8 620 326.7 1 —13 —25. 5? 11.7 119 48.3 185 85. 251 121.7 317 158.3 630 332.2 —12 —24.4 54 12.2 120 48.9 186 85.6 252 122.2 318 158.9 640 337 8 —11 -23.9 55 12.8 121 49.4 187 86.1 253 122.8 319 159 4 fi.'^n ^A% % '^%-'B,'i 56 13.3 122 50. 188 86.7 254 123.3 320 !l60. i 660 348.9 — 9—22.8 57 13.9 123 50.6 189 87.2 255 123.9 321 160.6 670 354 4 — 8 "- " iii 58 14.4 124 51.1 190 87.8 256 124.4 322 161.1 680 360. — 7 —21.7 59 15. 125 51.7 191 88.3 257J125. ; 323 II6I.7 690 365.6 — 6 —21.1 60 15.6 126 52.2 192 88.9 258|125.6; 324 162.2 700 371 1 — 5 —20.6 61 16.1 127 52.8 193 89.4 259J126.1 325 il62.8 710 376 7 — 4 —20. 62 16.7 128 53.3 194 90. 260 126.71 326 1163.3 720 382.2 — 3 —19.4 63 17.2 129 53.9 195 90.6 261 127.2 327 163.9 730 387 8 — 2 -18.9 64 17.8 130 54.4 196 91.1 262 127.8 328 |l64.4 740 393 3 — 1 —18.3 65 18.3 131 55. 197 91.7 263 128.3 329 ;165. 750 398.9 -17.8 66 18.9 132 55.6 198 92.2 264 128.9 330 165.6 760 404 4 + 1 —17.2 67 19.4 133 56.1 199 92.8 265 129.4 331 166.1 770 410 2 —16.7 68 20. 134 56.7 200 93.3 266 130. i 332 166.7 780 ;415.6 3 —16.1 69 20.6 135 57.2 201 93.9 267 130.6 333 167.2 790 1421 1 4 —15.6 70 21.1 136 57.8 202 94.4 268 131.1! 334 167.8 800 426 7 5 —15. 71 21.7 137 58.3 203 95. 269 131.7 335 168.3 810 432.2 6 —14.4 72 22.2 138 58.9 204 95.6 270 132.2 336 168.9 820 437 8 7 -13.9 73 22.8 139 59.4 205 96.1 271 132.8! 337 169.4 830 443 3 8 —13.3 74 23.3 140 60. 206 96.7 272 133.3 338 170. 840 448 9 9 —12.8 75 23.9 141 60.6 207 97.2 273 133.9 339 1170.6! 850 454 4 10 —12.2 76 24.4 142 61.1 208 97.8 274 134.4 340 J171.1 860 460 11 —11.7 77 25. 143 61.7 i 209 98.3 275 135. II 341 1171 7 870 4an fi 12 —11.1 11 25.6 144 62.2 210 98.9 276 135.6' 342 172.2 880 471.1 13 —10.6 79 26.1 145 62.8 211 99.4 277 136.1 343 1 172.8 890 476 7 14 —10. 80 26.7 146 63.3 212 100. 278 136.7,1 344 173.3 900 482 2 15 — 9.4 81 27.2 147 63.9 213 100.6 279 137.2! 345 173.9 910 487.8 16 — 8.9 82 27.8 148 64.4 214 101.1 280 137.8 346 174.4 920 493 3 17 — 8.3 83 28.3 149 65. 215 101.7 281 138.3 347 175. ij 930 |498 9 18 — 7.8 84 28.9 150 65.6 216 102.2 282 138.91 348 175.6 940 !504.4 19 — 7.2 85 29.4 151 66.1 217 102.8 283 139.4 349 176.1 950 1510. 20 — 6.7 86 30. 152 66.7 218 103.3 284 140. 1 350 176.7 960 515 6 21 — 6.1 87 30.6 153 67.2 219 103.9 285 140.6' 351 177.2 970 521.1 22 — 5.6 88 31.1 154 67.8 220 104.4 286 141.1 352 177.8! 980 526.7 23 - 5. 89 31.7 155 68.3 221 105. 287 141.7! 353 78.3 990 532 2 24 — 4.4 90 32.2 156 68.9 222 105.6 288 142.2 354 1 78.9 1000 537 8 25 — 3.9 91 32.8 157 69.4 223 106.1 289 142.8) 355 |] 79.4 1010 i543 3 RepHnted by permission from •'Kent's Mechanical Engineers' Pocket Book. ELECTRIC INTERLOCKING HANDBOOK 393 TEMPERATURES, CENTIGRADE AND FAHRENHEIT c. F. C. F. C. F. li C. F. C. F. i C. F. C. I F. ^0- -40. 26 i 78.8 92 197.6 158 316.4 I24 435.2 290 554 950! 1742 —39 -38.2 27 80.6 93|199.4 159 318.2 225 437. 300 572 960 1760 -38- -36.4 28 ! 82.4 94 201.2 160 320. 226 438.8 310 590 970 1778 —37 -34.6 29 • 84.2 95 203. 161 321.8 227 440.6 320 608 980 1796 -36 -32.8 30 86. 96 204.8 162 323.6 228 442.4 330 626 990 1814 -35- -31. 31 ^ 87.8 97 206.6 163 325.4 229 444 2 340 644 1000 1832 —34 -29.2 32 89.6 98 208.4 164 327.2 230 446. 350 662 1010 1850 -33- -27.4 33 91.4 99 210.2 165 329. 231 447.8 360 680 1020 1868 —32 -25.6 34 ; 93.2 100 212. 166 330.8 232: 449.6 370 698 1030 1886 -31 - -23.8 35 i 95. 101 213.8 167 332.6 233 451.4 3«0 716 1040 1904 —30- -22. 36 ; 96.8 102 215.6 168 334.4 234 453.2 390 734 1050 1922 -29 -20.2 37 i 98.6 103 217.4 169 336.2 235 455. 400 752 1060 1940 -28- -18.4 38 100.4 104 219.2 170 338. 236; 456.8 410 770 1070 1958 -27- -16.6 39 102.2 105 221. 171 339.8 237 i 458.6 420 788 1080 197G -26- -14.8 40 104. 106 222.8 172 341.6 238 1 4C0.4 430 806 1090 1994 —25 -13. 41 105.8 107 224.6 173 343.4 2.39! 462.2 440 824 1100 2012 -24 -11.2 42 107.6 108 226 4 174 345.2 240 464. 450 842 1110 2030 —23- - 9.4 43 109.4 109 228.2 175 347. 241; 465.8 460 860 1120 2048 —22- - 7.6 44 111.2 110 230. 176 348.8 242' 467.6 470 878 1130 2066 -21 -5.8 45 113. 111231.8 177 350.6 243: 469.4 480 896 1140 2084 -20- -4. 46 114.8 112 233.6 178 352.4 244 i 471.2 490 914 1150 2102 —19- - 2.2 47 116.6 113 235.4 179 354.2 245' 473. 500 932 1160 2120 -18- -0.4 48 118.4 114 237.2 180 356. 2461 474.8 510 950 1170 2138 -17 + 1.4 49 ,120.2 115 239. 181 357.8 247, 476.6 520 968 1180 2156 -16 3 2 50 122. 116 240.8 182 359.6 248' 478.4 530 986 1190 2174 -15; 5. 51 1123.8 117 242.6 183 361.4 249: 480.2 540 1004 1200 2192 —14 6.8 52 125.6 118 244.4 184 363.2 25o: 482. 550 1022 1210 2210 — 13j 8.6 53 1127.4 119 246.2 185 36.5. 251: 483.8 560 1040 1220 2228 -12 10.4 54 1129.2 120 248. ! 186 366.8 252' 485.6 570 1058 1230 2246 -lli 12.2 55 Il31. ! 121249.8 187 368.6 253 i 487.4 580 1076 1240 2264 —10 14. 56 132.8 122 251.6 188 370.4 254 1 489.2 590 1094 1250 2282 -9- 15.8 57 134.6 123 253.4 189 372.2 255; 491. 600 1112 1260 2300 -^8; 17.6 58 136.4 124 255.2 190 374. 256 1 492.8 610 1130 1270 2318 19.4 59 138.2 125 257. 191 375.8 257 494.6 620 1148 1280 2336 -el 21.2 60 140. 126 258.8 192 377.6 258 496.4 630 1166 1290 2354 — 5: 23. 61 141.8 127 260.6 193 379.4 259 1 498.2 640 1184 1300 2372 — 4 24.8 62 143.6 128 262.4 194 381.2 260 ' 500. 650 1202 1310 2390 -3 26.6 63 145.4 129 2&4.2 195 383. 261 i 501.8 660 1220 1320 2408 — 2 28.4 64 147.2 130 266. 196 384.8 262 .503.6 670 1238 1330 2426 - 1 30.2 65 149. 131 267.8 197 386.6 263 505.4 680 1256 1340 2444 32. 66 150.8 132 269.6 198 388.4 264 507.2 690 1274 1350 2462 T 1 33.8 67 152.6 133 271.4 199 390.2 265 509. 700 1292 1360 2480 2 35.6 68 154.4 134 273.2 200 392. 266 510.8 710 1310 1370 2498 3 37.4 69 156.2 135 275. 201 393.8 267 512.6 720 1328 1380 2516 4 39.2 70 158. 136 276.8 202 395.0 268 514.4 730 1346 1390 2534 5, 41. : 71 159.8 137 278.6 203 397.4 269 516.2 740 13&4 1400 2552 e! 42.8 72 161.6 138 280.4 204 399.2 270 518. 750 1382 1410 2570 7; 44.6 73 163.4 139 282.2 205 401. 271 519.8 760 1400 1420 2588 8 46.4 74 165.2 140 284. 206 402.8 272 521.6 770 1418 1430 2606 9 48.2 75 167. 141 285.8 207 404.6 273 523.4 780 1436 1440 2624 10 50. 76 168.8 142 287.6 208 406.4 274 525.2 790 1454 1450 2642 11 51.8 77 1170.6 143 289.4 209 408.2 275 527. 800 1472 1460 2660 12! 53.6 78 ;172.4 144 291.2. 210 410. 276 528.8 810 1490 1470 2678 131 55.4 79 ;174.2 145 293. 211 411.8 277 530.6 820 1508 1480 2696 14 57.2 80 176. 146 294.8 212 413.6 278 532.4 830 1526 1490 2714 15 59. 81 177.8 147 296.6 213 415.4 279 534.2 840 1544 1500 2732 16 60.8 82 179.6 148 298.4 214 417.2 280 536. 850 1562 1510 2750 17 62.6 83 181.4 149 300.2 215 419. 281 537.8 860 1580 1520 2768 18 64.4 84 183.2 150 302. 216 420.8 282 539.6 870 1598 1530 2786 19, 66.2 85 185. 151 303.8 217 422.6 283 541.4 880 1616 1540 2804 20 68. 86 186.8 152 305.6 218 424.4 284 543.2 890 1634 1550 2822 21 69.8 87 188.6 153 307.4 219 426.2 285 545. 900 1652 1600 2912 22 71.6 88 190.4 154 309.2 220 428. 286 546.8 910 1670 16.50 3002 23 73.4 89 192.2 155 311. 221 429.8 287 548.6 920 1688 1700 3092 24 75.2 90 194. 156 3K. 8 222 431.6 288 550.4 930 1706 1750 3182 25 77. 91 195.8 157 314.6 223 433.4 289 552.2 940 1724 1300 3272 RepTlnliXl bu permission from "Kent's Mcclianical Enjineers' Pocket Book. 394 GENERAL RAILWAY SIGNAL COMPANY SQUARES. CL-BES. SQUARE ROOTS AND CUBE ROOTS OF NX^MBERS FROM 0.1 TO 100 Xo. Square Oihe Sq. Root Cube Root No. Square ^»- ^ St Cube Root 01 .01 .001 .3162 .4642 kl 9.61 29.79ll 1.761 l.«58 .15 .0225 .0034 .3873 .5313 li .2 10.24 32.768! 1.780 1 474 .2 .04 .006 .4472 .5848 .3 10.89 35.937| 1 817 39.304 1.844 42.875 1.871 1.489 .25 .0625 .0156 .500 .6300 .4 11.56 1.504 .3 .00 .027 .5477 .6694 .5 12.25 1.518 .35 .1225 .0429 .5916 .7047 .6 12.96 46.656 1.897 1.533 .4 .16 .064 .6325 .7368 .7 13.69 50.6535 1.924 1.547 .45 .2JB5 .0011 .6708 .7663 .8 14.44 54.8721 1.949 1.560 .5 .25 .125 .7071 .7937 .9 15.21 50.319! 1.975 1 574 .55 .3025 .1664 .7416 .8193 4. 16. 64. 2. 1.5874 .6 .36 .216 .7746 .8434 .1 16.81 68.921 2.025 1.601 .65 .^25 .2746 .8062 .8662 .2 17.64 74.068 2.049 1.613 .7 .49 .343 .8367 .8879 .3 18.49 79.507 2.074 1.626 .75 .56^ .4219 .8660 .9086 .4 19.36 85.184 2.098 1639 .8 .64 .512 .8944 .9283 .5 20.25 91.125 2.121 1.651 .85 .7225 .6141 .9219 .9473 .6 21.16 97.336! 2.145 1.663 .9 .81 .729 .9487 .9655 .7 22.00 103.823 2.168 1.675 .95 .9025 .8574 .9747 .9630 .8 23.04 110.592 2.191 1.687 1. 1. 1. 1- 1. .9 24.01 117.649 2.214 1.698 1.05 1.1«S 1.158 1.025 1.016 5. 25. 125. 2.2361 1.7100 1.1 1.21 1331 1.049 1032 .1 26.01 132.651 2.258 1.721 1.15 1.3225 1.521 1.072 1.048 .2 27.04 140.608 2.280 1.732 1.2 1 44 1.728 1.0% 1.063 .3 28.09 148.8771 2.302 1 744 1.25 1.5625 ! 1.953 1.118 1.077 ! .4 29.16 157.464 2.324 1 754 1.3 1.60 1 2.197 1.140 1.091 .5 30.25 166.375 2.345 1.765 1.35 1.8225 2.460 1.162 1.105 .6 31.36 175.616 2.366 1.776 1.4 1.96 2.744 1 183 1 119 .7 32.49 185. 19S 2.387 1.786 1.45 2 1025 1 3.049 1 204 1.132 .8 33.64 195.112! 2.406 1 797 1.5 2.25 1 3.375 1.2247 1.1447 .9 34.81 205 379 2.429 1.807 1.55 2.4025 J 3.72d 1 1.245 1.157 6. 36. 216. 2.4495 1.8171 l.« 2.56 4.096 1.265 1.170 .1 37.21 226.961 2.470 1.827 1.i 154.331 1895.4 57. 179.071 2551.8 ^>* 129.983 1344.5 Vi 154.723 1905.0 Vh 179.463 2563.0 ¥2 130.376 1352.7 % 155.116 1914.7 Vi 179.856 2574.2 ''a 130.769 1360.8 ¥2 155.509 1924.4 % 180.249 2585.4 % . 131.161 1369.0 % 155.902 1934.2 V2 180.642 2596.7 Vh 131.554 1377.2 % 156.294 1943.9 % 181.034 2608.0 42. 131.947 1385.4 Vh 156.687 1953.7 % 181.427 2619.4 % 132.340 1393.7 50. 157.080 1963.5 % 181.820 2630.7 Va 132.732 1402.0 Vi 157.472 1973.3 58. 182.212 2642.1 % 133.125 1410.3 Va. 157.865 1983.2 Vh 182.605 2653.5 y2 133.518 1418.6 % 158.258 1993.1 Vi 182.998 2664.9 ■ % 133.910 1427.0 Vz 158.650 2003.0 % 183.390 2676.4 % 134.303 1435.4 % 159.043 2012.9 V2 183.783 2687.8 Vii 134.696 1443.8 % 159.436 2022.8 % 184.176 2699.3 43. 135.088 1452.2 '/8 159.829 2032.8 % 184.569 2710.9 % 135.481 1460.7 51. 160.221 2042.8 % 184.961 2722.4 1/4 135.874 1469.1 ^ 160.614 2052.8 59. 185.354 2734.0 =5 8 136.267 1477.6 Vi 161.007 2062.9 Vh 1^.747 2745.6 Va 136.659 1486.2 % 161.399 2073.0 Va 186.139 2757.2 ^'s 137.052 1494.7 V2 161.792 2083.1 % 186.532 2768.8 ^4 137.445 1503.3 % 162.185 2093.2 y2 186.925 2780.5 % 137.837 1511.9 % 162.577 2103.3 % 187.317 2792.2 44. 138.230 1520.5 ys 162.970 2113.5 1 % 187.710 2803.9 y^ 138.623 1529.2 52. 163.363 2123.7 % 188.103 2815.7 Va 139.015 1537.9 Vh 163.756 2133.9 60. 188.496 2827.4 '^s 139.408 1546.6 Vi 164.148 2144.2 ; Vh 188.888 2839.2 1-2 139.801 1555.3 ^'h 164.541 2154.5 : Va •189.281 2851.0 ■"'C 140.194 1564.0 V2 164.934 2164.8 % 189.674 2862.9 «4 140.586 1572.8 % 165.326 2175.1 V2 190.066 2874.8 Vs 140.979 1581.6 % 165.719 2185.4 i % 190.459 2886.6 45. 141.372 1590.4 % 166.112 2195.8 ! % 190.852 2898.6 % 141.764 1599.3 53. 166.504 2206.2 Vh 191.244 2910.5 1^4 142.157 1608.2 Vs 166.897 2216.6 61. 191.637 2922.5 3/^ 142.550 1617.0 y. 167.290 2227.0 ^ 192.030 2934.5 V2 142.942 1626.0 % 167.683 2237.5 Va 192.423 2946.5 "'■> 143.335 1634.9 V2 168.075 2248.0 % 192.815 2958.5 ^4 143.728 1643.9 % 168.468 2258.5 y2 193.203 2970.6 Reprinted by permission from "Kent's Mechanical Engineers' Pocket Book.' 400 GENERAL RAILWAY SIGNAL COMPANY Diam. Circum. Area Diam. Circum. Area Diam. Circum. Area 61% 193 601 2982.7 69y2 218.341 3793.7 77% 243.081 4702.1 % 193.993' 2994.8 % 218.733 380/3 1 % 243.473 4717.3 % 194.386 3006.9 ^4 219.126 3821.0 % 243.866 4732.5 62. 194.779 3019.1 V8 219.519 3834.7 % 244.259 4747.8 % 195.171 3031.3 70. 219.911 3848.5 % 244.652 4763.1 195.564 3043.5 % 220.304 3862.2 78. 245.044 4778.4 % 195.957; 3055.7 ^ 220.697 3876.0 ^ 245.437 4793.7 V^ 196.350| 3068.0 % 221.090 3889.8 y* 245.830 4809.0 % 196:742 3080.3 Vi 221.482 3903.6 % 246.222 4824.4 % 197.135 3092.6 ' % 221.875 3917.5 246.615 4839.8 % 197.528 3104.9 I % 222.268 3931.4 % 247.008 4855.2 63. 197.920 3117.2 % 222.660 3945.3 % 247.400 4870.7 1^ 198.313 3129.6 ! 71. 223.053 3959.2 % 247.793 4886.2 ^4 198.706 3142.0 % 223.446 3973.1 79. 248.186 4901.7 9s - 199.098 3154.5 y* 223.838 3987.1 248.579 4917.2 ^2 199.491 3166.9 I 224.231 4001.1 y^ 248.971 4932.7 »/8 199.884 3179 4 224.624 4015.2 % 249.364 4948.3 % 200.277 3191.9 % 225.017 4029.2 y^ 249.757 4963.9 % 200.669 3204.4 225.409 4043.3 % 250.149 4979.5 04. 201.062 3217.0 % ' 225.802 4057.4 % 250.542 4995.2 \% 201.455 3229.6 72. 226.195 4071.5 % 250.935 5010.9 Vi 201.847 3242.2 % 226.587 4085.7 80. 251.327 5026.5 % 202.240 3254.8 V* 226.980 4099.8 % 251.720 5042.3 V2 202.633 3267.5 % 227.373 4114.0 ^ 252.113 5058.0 ^i 203.025 3280.1 ^ 227.765 4128.2 % 252.506 5073.8 % 203.418 3292.8 % 228.158 4142.5 % 252.898 5089.6 •/8 203.811 3305.6 % 228.551 4156.8 % 253.291 5105.4 65. 204.204 3318.3 % 228.944 4171.1 % 253.684 5121.2 ' % 204.596 3331.1 73. 229.336 4185.4 % 254.076 5137.1 Vi 204.989 3343.9 % 229.729 4199.7 81. 254.469 5153.0 % 205.3821 3356.7 y* 230.122 4214.1 254.862 5168.9 Va 205.774 3360.6 % 230.514 4228.5 % 255.254 5184.9 % 206.167 3382.4 % 230.907 4242.9 % 255.647 5200.8 % 206.560 3395.3 % 231.300 4257.4 14 256.040 5216.8 '/S 206.952 3408.2 % 231.692 4271.8 % 256.433 5232.8 66. 207.345 3421.2 % 232.085 4286.3 a^ 256.825 5248.9 >^ 207.738 3434.2 74. 232.478 4300.8 % 25r218 5264.9 »r4 208.131 3447.2 ya 232.871 4315.4 82. 257.611 5281.0 % 208.523 3460.2 u 233.263 4329.9 % 258 003 5297.1 % 208.916 3473.2 % 233.656 4344.5 258.396 5313.3 % 209.309; 3486.3 % 234.049 4359.2 % 258.789 5329.4 % 209.701 3499.4 % 234.441 4373.8 yi 259.181. 5345.6 T^ 210.094 3512.5 % 234.834 4388.5 % 259.574 5361.8 67. 210.487; 3525.7 210.879! 3538.8 % 235.227 4403.1 .% 259.967 5378.1 % 75. 235.619 4417.9 % 260.359 5394.3 »r4 211.272 X>52.0 y» 236 012 4432.6 83. 260.752 5410.6 % 211.665 3565.2 y* 236.405 4447.4 % 261.145 5426.9 % 212.058 3578.5 % 236.798 4462.2 y* 261.538 5443.3 212.450 3591.7 237.190 4477.0 % 261.930 5459.6 % 212.843' 3605.0 % 237.583 4491.8 % 262.323 5476.0 % 213.236 3618.3 % 237.976 4506.7 % 262.716 5492.4 68. 213.628; 3631.7 % 238.368 4521.5 % 263.108 5508.8 % 214.021; 3645.0 76. 238.761 4536.5 % 263.501 5525.3 V4 214.414 3658.4 % 239.154 4551.4 84. 263.894 5541.8 % 214.806; 3671.8 y* 239.546 4566.4 % 264.286 5558.3 % 215.199: 3685.3 % 239.939 4581.3 % 264.679 5574.8 % 215.592 3698.7 % 240.332 4596.3 % 265.072 5591.4 % 215.984 3712.2 % 240.725 4611.4 % 265.465 5607.9 % 216.377 3725.7 % 241.117 4626.4 % 265.857 5624.5 69. 216.770 3739.3 % 241.510 4641.5 % 266.250 5641.2 % 217.163 3752.8 | 77. 241.903 4656.6 % 266.643 5657.8 v* 217.555 3766.4 ' % 242.295 4671.8 85. 267.035 5674.5 % 217.948 3780.0 , % 242.688 4686.9 ] % 267.428 5691.2 Reprinted by permission from "Kent's MecMnica: Engineers' Pocket Book." ELECTRIC INTERLOCKING HANDBOOK 401 Dlam. Circum. i Area Diam. Circum. Area Diam. Circum. ; Area 1 85V4 267.821 5707.9 90V4 283.529. 6397.1 96V4 299.237I 7125.6 % 268.213 5724.7 % 283.921 6414.9 % 299.6291 7144.3 Vo 268.606 5741.5 V2 284.314 6432.6 300.022 7163.0 •Is 268.999 5758.3 % 284.707 6450.4 % 300.415! 7181.8 1 i?i 269.392 5775.1 % 285.100 6468.2 % 300.807 i 7200.6 269.784 5791.9 % 285.492 6486.0 % 301.200 7219.4 86."* 270.177 5808.8 91. 285.885 6503.9 96. 301.593 , 7238.2 ^k 270.570 5825.7. ^% 286.278 6521.8 Vs 301.986 7257.1 1.4 270.962 5842.6 H 286.670' 6539.7 Vi 302.378 j 7276.0 k 271.353 5859.6 % 287.063 6557.6 % 302.771 1 7294.9 1/2 271.748 5876.5 V2 287.456 6575.5 V2 303. IW 7313.8 ■^s 272.140 5893.5 % 287.848 6593.5 % 303.556 ' 7332.8 -i 272.533 5910.6 288.241 6611.5 % 303.949 7351.8 272.926 5927.6 % 288.634 6629.6 % 304.342 7370.8 87.' 273.319 5944.7 92. 289.027 6647.6 97. 304.734 7389.8 1.8 273.711 5961.8 Vs 289.419 6665.7 Vs 305.1271 7408.9 1 1,4 274.104 5978.9 y* 289.812 6683.8 Vi 305.520 7428.0 ■^•s 274.497 5996.0 ,% 290.205 6701.9 % 305.913 7447.1 I V, 274.889 6013.2 ^ 290.597 6720.1 V2 306.305 7466.2 •■"^s 275.282 6030.4 % 290.990 6738.2 % 306.698 7485.3 L'i 275.675 6047.6- % 291.383 6756.4 % 307.091 7504.5 Vs 276.067 6064.9 % 291.775 6774.7 Vs 307.483 7523.7 88. 276.460 6082.1 93. 292.168 6792.9 98. 307.876 7543.0 Vs 276.853 6099.4 Vh 292.561 6811.2 % 308.269 7562.2 Vi 277.246 6116.7 . Vi 292.954 6829.5 Vi 308.661 7581.5 3^ 277.638 6134.1 % 293.346 6847.8 % 309.054 7600.8 V2 278.031 6151.4 V2 293.739 6866.1 V2 309.447 7620.1 % 278.424 6168.8 % 294.132 6884.5 % 309.840 7639.5 34 278.816 6186.2 % 294.524 6902.9 % 310.232 7658.9 ',8 279.209 6203.7 % 294.917 6921.3 % 310.625 7678.3 89. 279.602 6221.1 94. 295.310 6939.8 99. 311.018 7697.7 Vh 279.994 6238.6 Vs 295.702 6958.2 Vs 311.410 7717.1 Vi 280.387 6256.1 Vl 296.095 6976.7 Vi 311.803 7736.6 % 280.780 6273.7 % 296.488 6995.3 % 312.196 7756.1 V2 281.173 6291.2 V2 296.881 7013.8 V2 312.588 7775.6 % 281.565 6308.8 % 297.273 7032.4 312.981 7795.2 % 281.958 6326.4 % 297.666 7051.0 % 313.374 7814.8 % 282.351 6344.1 % 298.059 7069.6 % 313.767 7834.4 90. 282.743 6361.7 96. 298.451 7088.2 100. 314.159 7854.0 % 283.136 6379.4 Vs 298.844 7106.9 RepriKied by perrr*isionfrom "Kent's Mechanical Engineers' Pocket Book," SECTION XVITI APPENDIX COVERING REPRINT OF PREFACE FROM TAYLOR (G. R S) CATALOGUE NO. 1, INFORMATION REQUIRED FOR THE DRAWING UP OF INTERLOCKING ESTIMATES, AND A LIST OF G. R. S. ELECTRIC INTERLOCKING LEVERS INSTALLED APPENDIX REPRINT OF PREFACE From Catalogue No. 1 (1902), Taylor Signal Company, Buffalo, N. Y. Taylor Signal Company acquired by the General Rail- way Signal Company in 1904. IN the last few years there has been a phenomenal increase in tonnage hauled on American railways, necessitating the purchase of more and better engines and cars of larger capacity, equipped with the best safety devices. Enor- mous sums have been expended in taking out curves, cutting down grades, laying additional main tracks, putting in new sidings, and providing improved terminal facilities. But, notwithstanding all these improvements, many hnes find it impossible to handle their business with sufficient dispatch to avoid congestion. This fact has led many progressive Ameri- can railway managers to realize that if they are to secure the best and most economical returns from the great expenditures made for motive power, car equipment, and tracks, suitable means must be provided to enable their trains to move with a minimum of delays and a maximum of safety; and this can only be realized when train orders are supplanted by an up-to- date block system and hand operated switches by a modern system of interlocking. The very highest development of the art of signaling has been reached in this country, but no American railway is nearly §0 thoroughly equipped with signaling as is the average English line. This lack of signal equipment will be better comprehended after considering some simple statistics. The first interlocking plant installed on the London and Northwestern Railway was put in service in 1859; fourteen years later^ in 1873, there were in use on that line alone 13,000 levers. At the same date there was not a single interlocking plant in use in the United States, the first plant in this country having been installed in the year 1874 by Messrs. Toucy and Buchanan at Spuyten Duyvil Junction, in New York City. At the present time (1902) there are in use on the 1,800 miles of line of the London and Northwestern Railway ap- proximately 36,000 interlocked levers, or an average of about twenty levers per mile of line, whereas there are only about 40,000 in use on all lines of the United States, or, approxi- mately, one lever to five miles of line, or about 1 per cent, of the number of levers per mile used on the London and Northwestern Railway. When it is remembered that probably more than one-half of the interlocked levers in use in this country are at grade crossings, leaving fewer than 20,000 levers used for station, yard and terminal work, whereas practically the entire 36,000 406 GENERAL RAILWAY SIGNAL COMPANY on the L. & N. W. are used for such work alone, it will be recog- nized that American railways are in general very poorly pro- vided with modem signal appliances. In fact, there is probably to-day not a single American railway that is nearly so thor- oughly equipped as the London and Northwestern was twenty- seven years ago, though, as might be expected, the devices in use on American lines having properly organized signal depart- ments, capable of making suitable specifications, compare favorably with the best in use on European Unes and, in nu- merous instances, large power plants are in use which are supe- rior to anything ever de\ased abroad. There can be no question as to the inability of most of our raUways to move their trains with proper safety and dispatch during times when traffic is heavy; no competent railway operating oflBcer doubts that proper systems of signaling would greatly aid in the safer and more rapid movement of trains and, while there are probably few American railway men who recognize fully how very far behind the best European lines our fines are in respect to the completeness of their signal equipment, this is becoming better understood every year and there is reason to believe that our most progressive lines will not much longer continue to limit the applications of interlocking to the protection of grade crossings with here and there a junction or y^d plant. Such being the case, it is probable that more signaling will be done in the near future than has ever before been done in this coimtry and American railway managers will, therefore, find it greatly to their advantage to give serious consideration to the determination of what system of interlocking they can best use. The earliest system employed and that in most general use at this time is the so-called "mechanical interlocking" in which the switches or signals are manually worked by means of interlocked levers connected with them by pipe or wire lines. When properly installed, this system has given satisfactory results'^ but, unfortunately, in the effort of railway men to secure cheap appliances and in the stress of competition be- tween the various manufacturers of signaling devices, a great many of the installations made in this country are very imper- fect and unsafe. Experience has showTi that, in order to secure a reasonable degree of safety, it is absolutely essential that the following requirements be met : All derails, movable point frogs, locks, switches and home signals should be worked by pipe ; no signal should be worked by a single wire; all pipe and wire lines should be automatic- ally compensated ; all derails, movable point frogs and facing f)oint switches should be pro\ided with duplex facing point ocks; all cranks and pipe compensators should be fixed on strong foundations set in best quality concrete; no facing point switch more than 600 feet from the tower should be ELECTRIC INTERLOCKING HANDBOOK . 407 taken into the system; no lever should be overloaded by putting on it such a number of switches and bars as to pre- vent a man of average strength from throwing it with one hand. Where these and other proper specifications have been fol- lowed, fair results have been obtained, though it has long been recognized by American railway operating officials that this system has inherent defects that render it, under certain conditions, unsafe. For example, in the event of the breakage of a pipe or wire operating a signal, there can be no absolute assurance that such breakage will be known by the leverman or that such signal will occupy a position corresponding with that of its lever or that it will not indicate "line clear" when, its lever being normal, another and opposing signal is set at "line clear." The fatigue incident to working mechanical levers is very great, so that it is frequently necessary to employ three eight- hour levermen for a comparatively small plant where the number of lever movements is considerable; if the plant is very large, it is sometimes necessary to employ as many as eight men on each of three shifts. Moreover, under certain conditions it is very costly to operate such a system. For example, in cases where the distance between the extreme switches to be operated is over 1,600 feet, it is generally necessary to provide two mechanical inter-* locking towers, each with its own set of levermen, as it is neither safe nor practicable to work such switches from one tower. It is interesting to note in this connection that under the English Board of Trade requirements, which are wisely drawn and rigidly enforced, no facing point switch may be operated at a distance exceeding 540 feet from the tower. Even at this distance it is considered that ordinary pipe lines are not sufficiently strong or safe and many English lines now employ a steel channel section, cut to eighteen foot lengths and jointed by means of fish plates secured by six one-half inch bolts, this construction admitting of ready detection of rods weakened by corrosion and of their easy removal. In order to overcome these and other disadvantages inherent in systems of mechanical interlocking, the "pneumatic system " was devised by Mr. George Westinghouse, Jr., the first working installation having been made at the crossing of the P. and R. and L. V. Railways, near Bound Brook, N. J., in 1884. At the present time two varieties of this system are in use, one, popularly known as the "electro-pneumatic," in which air compressed to a working pressure of about sixty pounds is employed for moving switches and signals and in which the release locking is effected by electro-magnetic means ; and the other, popularly known as the "low pressure pneumatic," in which air at a pressure of about twenty pounds is used for operation and in which compressed air effects the release locking. 408 GENERAL RAILWAY SIGNAL COMPANY Some of the advantages claimed for this system are as follows : The ability to operate switches and signals at any desired distance from the cabin ; that switches are actually required to be moved and securely locked in the proper position before a signal governing traffic over them can be cleared ; that each signal, when cleared, automatically locks the lever operating it in such manner as to prevent the release of levers controlling conflicting signals and switches, until such signal has been again placed completely at danger, thus effectually providing against the simultaneous display of two conflicting clear signals; that, there being no moving parts between cabin and switches and signals, wear of mechanism, lost motion and the troublesome and dangerous effects of expansion and con- traction of mechanically operated pipes and wires are all eliminated; that much less room is required for leadout con- nections than in a mechanical plant and much valuable space is thereby saved; that cabins of much smaller and lighter design are used ; that the operation of the machine requires so little physical exertion that one man can do the work that would in a mechanical plant require three or four. There can be no doubt that both varieties of the pneumatic system are far better adapted for the working of large plants than the mechanical as both largely fulfill the claims above •referred to. It is, however, found that in the electro-pneumatic system a cross between the release locking (commonly known as "indi- cation") wire and the common return wire (or ground), will have the same effect as would the closing of the indication cir- cuit in the proper manner, thus giving a false indication, which in view of the fact that the safety of any power interlocking depends upon the reliability of its indications, is highly objec- tionable. It is also found that where the indication is given by means of compressed air the release locking is often effected very slowly in cases where switches or signals are located at a considerable distance from the tower and this, at a busy plant, is also very objectionable. Another disadvantage of the low pressure pneumatic system is that if a switch, meeting any obstruction, fails to complete its movement and to give indication, it is necessary either for a repairman to go immediately to -the switch and operate it by hand or for the leverman to force the indication, which is often done and is evidently dangerous. Thus, in one style of the pneumatic system there is the defect due to possibility of false indication and in the other the defect due to slow indi- cation and to inability to reverse a switch which has not fully completed its movement. Some other disadvantages of the pneumatic systems are as follows : Liability to freezing of pipes and valves in extreme cold weather; high cost of furnishing power; danger of throwing near switches under trains when, owing to extreme cold ELECTRIC INTERLOCKING HANDBOOK 409 weather, it is necessary to maintain higher than normal pres- sures in order to be able to work switches farthest from tower ; high cost of maintenance owing to rapid deterioration of iron pipe lines placed underground and subjected to action, of various salts and alkalies found in soil and to electrolytic action from electric railway and lighting circuits; difficulty and cost of locating leaks and breaks in pipe lines under ground ; extremely high cost of installing and operating medium sized and small plants or a small number of switches or signals located at a considerable distance from the tower in a large plant. To overcome these and other objectionable features of the pneumatic system, the "electric" system was devised. This system, the invention of Mr, John D. Taylor of Chilli- cothe, Ohio, was first installed by him on the B. & O. S. W. R'y at East Norwood, near Cincinnati, Ohio, in 1891; in 1893 certain improvements were introduced by him in the methods of giving indications, the installation remaining otherwise as originally made. For some years afte-- 1893, only a few small installations were made by Mr. Taylo: owing to lack of sufficient capital to develop his inventions on a large scale, but in May, 1900, the Taylor Signal Company was organized in Buffalo, N. Y., and since that time a great number of installations, varying in size from the equivalent of 6 to 225 mechanical levers, have been made on important lines of railway in the United States and Europe. In the Taylor (G. R. S.) electric system, switches and signals are operated by means of electric motors, the current for these motors being furnished generally by a storage battery, charged from a dynamo driven by an electric motor or gas engine. The release locking is effected by an electro-magnetic device placed under each interlocking lever and actuated by a dynamic current furnished by the switch or signal motor controlled by such lever, when and only when a switch has moved to a position corresponding with that of the lever and is bolt locked in that position or when a signal arm has moved to its full danger position. Crosses between an indication wire and common return wire (or ground) or any other wire of the system, can at worst only prevent the giving of indication and cannot by any possibility result in the giving of a false clear indication as can occur in other systems employing electro- magnetic indications. Moreover, in this system, indications are given instantaneously upon completion of locking of switch or of movement of signal to its stop position, irrespective of the distance of such switch or signal from the tower, thus effecting a great saving in the time required by any system using pneumatic indications, to set up a route. If, when a switch is thrown, it fails to complete its move- ment owing to some obstruction between point and stock rail, or for any cause whatever, the switch can be restored by the leverman to its original position and another effort can 410 GENERAL RAILWAY SIGNAL COMPANY be made to perform the desired movement, ofttim.es thus avoiding the necessity, so frequently met with in the low pressure pneumatic system, of sending a man out to throw the switch by hand or of forcing the indication. The electric is the only power system that can be satisfac- torily employed for the operation of plants having a small number of switches and signals. It is in service where as few as six working levers are employed and is perfectly adapted for use at all junctions, crossings, drawbridges, tunnels, sta- tions, yards, passing sidings, etc., where the distance between extreme switches or signals is greater than can be safely covered with a mechanical plant, even though there be only a very few signals and switches to be operated. For example, consider the two following diagrams, the first one showing arrangement of passing sidings on a single track and the other on a double track line : Tire 5TAT10N-A 1000 to 7000 STATIONS CGR5lI9I3) On a few of the best signaled American railways the switches and signals immediately adjacent to the station A or B, would be worked by a mechanical interlocking plant, but owing to the great cost of operating an additional mechanical interlock- ing plant at each of the extreme switches and the prohibitive cost of putting in a pneumatic power system by which all the switches and signals could be worked from the station, the inlet switches are left to be worked by the trainmen, necessi- tating the stopping of their trains; and if, as sometimes happens, such stoppage occurs on a bad grade, heavy trains may break in two in starting up. Every practical railway man will at once recognize the tremendous advantage that would be gained if these extreme switches, together with their proper signals, could be safely and economically worked from ELECTRIC INTERLOCKING HANDBOOK 411 the station, thereby enabling trains to pass onto and out of passing sidings at speed and in absolute safety. With the Taylor (G. R. S.) electric system this can be effected at a rela- tively small cost, and, in conjunction with a system of auto- matic, electric, track circuit block signals in use on the open road, where there are no switches, this forms the ideal lock and block system and one, which we believe is destined to replace all others both in this country and in Europe. In the electric system, the cost of producing power for the operation of switches and signals rarely or never exceeds 1 per cent, of the cost in any other power system doing an equal amount of work. For example, if in a system using compressed air, the cost of coal and services of men employed in running power plant is 400 dollars per month, the total cost of producing power for an electric plant doing precisely the same work will rarely or never exceed four dollars monthly. In this connection it will be interesting to note that at the South Englewood Taylor (G. R. S.) interlocking plant on the C.R.I.&P.R. R., where the average daily number of switches moved and signals cleared is 2,250, the consumption of gaso- line for running engine for charging storage batteries, was sixty-eight gallons in eighty-six days, or one gallon for 2,845 switch and signal operations. At Sixteenth and Clark streets, Chicago, Taylor (G. R. S.) interlocking plant at the crossing of the St. Charles Air Line with the C. R. I. & P. and L. S. & M. S. R'ys, where the movement exceeds 600 trains daily, the consumption of gasoline during 153 days was 222 gallons for 642,600 switch and signal movements or 2,894 per gallon or about 326 movements for one cent for power. The cost of maintenance and renewals in an electric plant is only a small percentage of the cost in any other power plant. This can be readily understood from the fact that more feet of electrical conductors are employed in the electro-pneumatic system than are used in the Taylor (G. R. S.) system and there are all the pneumatic pipes; and, in the low pressure pneu- matic system, more feet of iron pipe are used than feet of elec- tric conductors in the Taylor (G. R. S.) system, and any one having experience with the rapid deterioration of iron pipes placed in the soils found about railways and subject to elec- trolysis, will have no difficulty in understanding how much shorter lived these underground pipes will be than well insulated copper wires placed in a suitable conduit above ground. Nor is it hard to understand how much more difficult and costly it will be to make repairs to such pipe placed several feet under- ground than it will be to repair a break or leak in a wire placed in a suitable conduit above ground. In this connection, it is interesting to note that the B. & 0. S. W. R. R., which was the first to install the Taylor (G. R. S.) system, has found it far cheaper to maintain than an ordinary- mechanical plant, and this is particularly true where, through change in grade or alignment of tracks, any changes are 412 GENERAL RAILWAY SIGNAL COMPANY required in the interlocking plant, such changes being many- times more costly in any other system than in the Taylor (G. R. S.) electric. Moreover, with the improved devices and methods of installation now used in this system, a far better showing will be made. The operation of the electric system is absolutely unaffected by change in temperature, whereas pneumatic systems some- times experience serious difficulties owing to condensation and freezing of moisture contained in the compressed air, by which the mechanism becomes clogged .and its working pre- vented. Even where the working is not absolutely prevented under these conditions, it frequently becomes necessary to raise the pressure so high in order to compensate for losses in pressure at distant switches, that there is danger of throwing near switches under train, in case leverman makes an improper movement at such a time, as it is certain that as generally installed, detector bar connections are not sufficiently strong to resist any considerable increase above the normal working pressure in a pneumatic plant. It is therefore doubtful whether, during extreme cold weather, it is ever safe to attempt to work from one pneumatic machine, s\\itches and signal, located so far from the tower as to require any increase over normal working pressure. Unquestionably, the safer practice, at such times,' is to temporarily abandon the working of such switches and signals, as is often done, though this, of course, causes much troublesome delay and expense. In the electric ^stem no such condition exists, as the "electric pressure" is exactly the same on the switch or signal motor located at a distance of 5,000 feet as on one located 500 feet from the tower ; moreover, the system is so arranged that the throwing of a switch lever while train is over the switch would cause the blowing of a fuse on the machine, thereby opening the circuit. In the foregoing statement no effort has been made to de- scribe in detail the appliances and circuits employed in the Taylor (G. R. S.) electric system of interlocking; our object has been solely to point out the need of signal equipment on American railways and to state, without prejudice, the prin- cipal merits and defects of the several interlocking systems at present employed, in order to aid such railway officials as have not had opportunity to acquaint themselves with the facts above set forth to make an intelligent comparison between such systems. ' The Taylor (G. R. S.) electric system is in the fullest accord wth modem engineering practice which has shown, after years ot experiment, that transmission of power to a distance can be more satisfactorily accomplished by means of electricity than by any other agency and, while there is no reason to doubt that this system will be improved in the future as in the past, we feel warranted in claiming at the present time ELECTRIC INTERLOCKING HANDBOOK 413 that it represents the very highest development of the art of signaling, embodying features of safety, economy and general applicability not possessed by any other system in use in this country or abroad. Taylor Signal Company. (General Railway Signal Company.) INFORMATION TO BE FURNISHED BY THE RAILWAY COMPANY WHEN REQUESTING AN ESTIMATE. ON ELECTRIC INTERLOCKING In order to prepare promptly an accurate estimate on a pro- posed installation of electric interlocking, it is necessary that definite information on certain items be furnished by the Rail- way Company with the request for a proposal.' This informa- tion can best be covered by a specification together with certain plans. It is not necessary for each individual railroad to prepare a specification form as the Railway Signal Association adopted, in 1910, a very complete specification covering this practice. The specification has been prepared by a committee of men, actively engaged in railway signal work, and its use is heartily recommended. It can be secured by reference to the Manual of the Railway Signal Association issued in 1912. It has, of course, been necessary in drawing up this specification to leave optional a number of items, definite information on which should be given with " each request for an estimate. Attention is especially directed to certain points essential to the preparation of estimates, covered by sections of the specification as follows : 3. "Drawings." A track plan should be furnished giving very completely the information under sub-paragraph 1. The symbols which have been adopted by the Railway Signal Association as shown on pages 348 to 359 of this Handbook should be used. The infor- mation called for in sub-paragraphs 2, 3 and 4 should be given if possible, although this is not absolutely necessary. 7. "Materials to be furnished and work to he done by and at the expense of the Purchaser." Consideration should be given to the items listed in this paragraph and note made of any deviation therefrom. 18. "Transportation." A definite statement should be made as to whether trans- portation is to be furnished for men, tools and materials or for either. 414 GENERAL RAILWAY SIGNAL COMPANY 50. "Building foundations." 51. "Interlocking station." 52. "Power house." It should be clearly stated whether the contractor is to erect the buildings and their foundations, the dimensions and specifications being given if such is the case. 54. "Lighting for hu^'ldings." When electric lighting for any of the buildings is desired, paragraphs a, b, c and d should be filled out. 60. "Plant." {Power Plant.) 61. "Engine." 70. "Motor." 85. " Storage battery." Definite information must be given as to the power supply The ampere hour capacity and number of cells of the battery should be specified as well as the capacity of any charging apparatus desired. Data on pages 154 to 159 of this Handbook will be of a3sistan(?e in determining the proper capacities for the battery and charging apparatus. 100. "Machine." (Interlocking Machine.) While a properly prepared track plan will determine the size and arrangement of levers in the interlocking machine, it will be necessary to specify any spare spaces or spare levers required in the event of this information not being shown on the plan. 502. " Track circuits." The number and arrangement of track circuits to be installed should be shown on the plans or covered in the specification. 506. "Electric lighting circuits." The information called for in this section should te given, attention being called to pages 127 to 130 in this Handbook. 510. "Special circuits." Typical plans of special circuits may be furnished under this section or the circuit requirements stated, in which event the contractor will submit typical proposed circuits with the estimate. Pages 133 to 139 of this Handbook are devoted to Electric Locking circuits, the data being based on the R. S. A. classification of the different types of circuits. 521. "Size." {Wire and Wiring.) The data as to size of wires under paragraph " f " should be given when track circuits are to be installed. ELECTRIC INTERLOCKING HANDBOOK 415 ELECTRIC INTERLOCKING LEVERS INSTALLED AND UNDER CONTRACT January 1, 1913 Number Total Name of Road of Plants Levers Atchinson, Topeka & Santa Fe R'y, 40 1348 Atlanta, Birmingham & Atlantic R'y, 1 48 Atlanta Terminal Station, 2 184 Baltimore & Ohio, 19 880 Birmingham Terminal Station, 1 144 Buffalo Creek R. R., 1 84 Canadian Pacific R'y, 3 40 Central of Georgia R'y, 1 52 Central R. R. of New Jersey, 1 28 Chattanooga Union Station Co., 1 120 Chesapeake & Ohio R'y, 7 212 Chicago & Alton R. R., . . 2 108 Chicago & Eastern Illinois R. R., 4 136 Chicago & Milwaukee Electric, 1 32 Chicago & Northwestern R'y, 35 2100 Chicago & Western Indiana R. R., ...... 1 24 Chicago, BurHngton & Quincy R. R., 7 464 Chicago Great Western R. R., 5 128 Chicago, Indianapolis & Louisville R'y (Monon), 1 28 Chicago, Milwaukee & St. Paul R'y, 10 416 Chicago, Rock Island & Pacific R'y, 5 494 Chicago, St. Paul, Minneapolis & Omaha R'y, 5 80 Cincinnati, New Orleans & Texas Pacific R'y, . . 6 208 Cleveland, Cincinnati, Chicago & St. Louis R'y, . 13 556 Copper Range R. R., 1 40 Cumberland Valley R. R., 3 24 Delaware & Hudson Co 2 64 Department of Public Works, British Columbia, 1 28 Detroit & Toledo Construction Co., 1 32 Detroit River Tunnel Co., 4 264 Elgin, Joliet & Eastern R'y, 2 72 Erie R. R., . . . 11 614 Galveston, Harrisburg & San Antonio R'y, ... 1 40 Grand Trunk R'y, 2 60 Great Northern R'y, 6 200 Gulf, Colorado & Santa Fe R'y, 1 48 Houston & Texas Central R. R., 8 248 Houston Belt & Terminal R'y, 3 140 Hudson & Manhattan R. R., 10 128 Illinois Central R. R., 20 824 Kansas City Terminal R'y, 1 56 Kentucky & Indiana Terminal R. R., 1 56 Lake Shore & Michigan Southern R'y, 28 1778 Lehigh Valley R. R., 9 384 Long Island R. R., 2 68 Louisville & Nashville R. R.. 4 160 416 GENERAL RAILWAY SIGNAL COLfPAN^' Number Name of Road of Plants Louisiana R'y & Navigation Co 1 Michigan Central R. R., 6 Missouri Pacific R'y, 1 Morgan's Louisiana & Texas R. R. & S. S. Co., . 1 Nashville, Chattanooga & St. Louis R'y 1 New York Central & Hudson River R. R., . . . 32 New York, New Haven & Hartford R. R., . . . 3 Norfolk & Western R'y, 1 Northern Pacific R'y 7 Northwestern Elevated R. R., 1 Oregon Short Line, 1 Oregon, Washington R. R. & Navigation Co., . . 2 Pacific Electric R'y, 4 Pecos & North Texas Ry., 1 Pennsylvania Lines West of Pittsbui^h, .... 16 Pennsylvania R. R., 3 Peoria & Pekin Union R'y 1 Pere Marquette R. R 6 Pittsburgh & Lake Erie R. R., 4 Railway Signal Co. , of Canada ( Grand Trunk R'y), 1 &in Francisco-Oakland Terminal R'y, 2 Savannah Union Station, 2 Southern Indiana R'y, 1 Southern Pacific Co., 17 Southern Railway, 1 Spokane & Inland Empire R. R 1 Terminal R. R. Assn. of St. Louis, 6 Texas & Pacific R'y 1 Tidewater & Western R. R., ........ . 1 Toledo & Ohio Central R. R., 2 Toledo R'y & Light Co., 1 Toledo R'y & Terminal Co 2 Toronto, Hamilton & Buffalo R'y, 1 Union Pacific R. R., 6 Washington. Baltimore & Annapolis Electric R'y, 1 Western Pacific R'y, * . . 6 Wisconsin Central R. R., 3 Grand Total, .440 21,370 INDEX INDEX Alternating A Alternating current appliances, 107- 124 Alternating current relays (see relays) Angles, measures of. 388 Apparatus (see under name of mate- rial) . Appendix: Information for estimating, 413, 414. Interlocking plants installed, list of, 415, 416. Reprint of Preface from Taylor (G. R. S.) Catalogue No. 1, 405-413. Approach locking, 136, 138 (see also electric locking). A. R A. rail sections, 375. Arcs, measures of, 388. Arrester, lightning, 371. A. S. C E. rail sections, 375. Avoirdupois weight, 388. Ballast, definition of grades of, 273. Batteries ; Primary, caustic soda cell: Action of, 285, 287. Care of, 287. Description of, 285. Illustration of, 286. R S. A. cell, 286. R. S, A. specifications for, 287, 288. Symbols for, 351, 359. Uses of, 285. Primary, dry cell: Care of, 294. Description of, 294. Symbols for, 351, 359. Uses of, 293. Primary, gravity cell: Action of, 289. Care of, 293. Chutes for, 292, 293. Coppers for, R. S. A., 291. Descr'ption of, 289. Symbols for, 351, 359. Uses of, 288. Zinc for, R. S. A., 290. Secondary, lead type storage: Broken jars, 153. Batteries Batteries : — {Con.) Secondary, lead type .storage: Capacity required for electric lighting, 155, 156. Capacity required for function operation, 154, 155. Capacity required for G. R. S. plants, 154-158. Capacity required for G. R. S. plants, table, 158. Capacity required for indica- tors, locks, etc., 156. Capacity required for operating switchboard, 155. Capacity, reserve, 156, 157. Cell cover for, 146. Cells, number required for inter- locking plants, 38. Charging apparatus for, 39, 40, 159-166. Charging circuit for, 163. Charging instructions for, 151, 152. Charging switch for, 160. Charging rate of, 146, 159. Cupboards for, 38, 158. Description of, 145. Dimensions of R. S. A. cell, 146. Discharging, instructions for, 152. Electrolyte for, 146, 148, 149. Formula for determining size of, 157, 158. Function constants, table of, 155. Housing of, 37, 38. Illustrations of, 37, 38, 145, 146, 158. Important points in care of, 153, 154. Indications of trouble in, 153. Initial charge of, 150. Inspection of, 153. Installation, R. S. A. directions for, 148-151. Jar for, 146. Large capacity cells for, 151. Location at interlocking plants, 37. Low voltage, uses of, 39. Operation, R. S. A. instructions for, 151-154. Pilot cell for, 151. Racks for, 37, 145. 420 INDEX Batteries Batteries: — (Con.) Secondary, lead type storage: . Readings of, 153. Reserve capacity required, 156, 157. R. S. A. directions for installa- tion, 148-151. R. S. A. instructions for opera- tion of, 151-154. R. S. A. specifications for, 147, 148. Sand tray for, 146. Specifications for, R. S. A., 147, 148. S>-mbob for, 359. Trouble, indications of. 153. Two plate cells for, 150, 151. Uses at interlocking plants, 38, 39. Voltage of, 38, 39. Weights of cells for, 146. Battery charging apparatus (see charging apparatus). Battery chutes: Illustrations of. 292, 293. Symbols for, 351. Uses of. 293. Weights of, 367. Battery chaii^ng switch, 160, 161. Baume's hydrometer, compared with specific gravities, 384. Bearing, for high or dwarf signal, 79. Belting, 373, 374. Blades for upper quadrant signals. 249. Board feet required for trunking. 315. Board measure, table of. 383. Bolts, dimen^ons of, 3S0. Bonds, impedance (see impedance bonds). Bond wires and channel pins, quan- tities required, ^78. Boxes: Junction (see junction boxes). Measuring concrete. 323. Relay (see relay boxes). Switch (see switch circuit con- trollers). Bracket masts, 243. Bracket posts (see posts). Bridge circuit closers ; Description of. 233. 234. Dimensions of, 233. Operation of. 233, 234. Symbols for, 357. Bridge masts. 243. Circuits Capacity of storage batteries, 154- 158 (see also battery, stor- age). Caustic soda cell. 285-288 (see also battery, primary). Centigrade temperatures compared with Fahrenheit. 392. CSiannel pins and bond wires, quan- tities required. 378. Charging apparatus, generators, driving units, etc.: Capacity required, 159. Circuits for, 163. Description of, 39, 40. Dimensions of. 168. 169. EflBciency of. 159. Floor space, required for, 159, 169. Input, 159. Illustrations of. 39. 40. 42, 43, 170. Installation data for. 159-181. Switchboards for, 40-46. Symbols for, 359. Weights of, 363. Chai^ng rheostat, 40. (Charging switch, battery. 160, 161. Charts, manipulation, 102, 103. Check locking. 140, 141. Chutes, battery (see battery chutes). Circuits: Approach, indication and sec- tion locking in combination. 138. Approach locking. 136. Alternating current track, double raU. 273. Alternating current track, angle rail, 114-119. Battery charging switch. 161. Charging, simplified. 163. Clieck locking. 140. 141. Cross protection, 8S. S9. Double rail A. C. track, 273. Klectric locking: Approach, indication and sec- tion locking in combination, 138. Approach locking, 136. Route locking. 135. Section locking 134. Stick, indication and section locking in combination, 139. Stick lock-ing, 137. Interiocking machine, 88. INDEX 421 Circuits Circuits : — {Con.) Motor connections: Model 2 switch machine, 201. Moc'ei 4 switch machine; 209. Operating : Model 2 and 3 dwarf signals, 83, 84. Model 2A high signal, 22-24. Model 2 and 4 switch machines, 19-22. Switchboards, 40-46. Pole changer: Model 2 switch machine, 203. Model 4 switch machine, 210. Route locking, 135. Section locking, 134. Signal : Description of, 22-24. Model 2 or 3 solenoid dwarf, 84. Model 2 solenoid dwarf, one arm, typio*!, 260. Model 2 solenoid dwarf, two arm, typical, 261. Model 3 solenoid dwarf, typi- cal, 262. Model 2 A, two position, non- automatic, simplified, 23. Model 2 A, two position, non- automatic, typical, 71, 254, 255. Model 2 A, two position, semi- automatic, typical, 73, 256- 259. Single rail A. C. track, 114- 119. Stick, indication and section locking in combination, 139. Stick locking, 137, Switchboard : Description of, 40^6. Combination power and opera- ting, 180. Oi}erating, 181. Operating, simplified diagram for, 45. Power, 176-178. Power, simplified diagram for, 43. Switch machine: Description of, 19-22. Double switch lever, 228. Model 2 or Model 4, 61. Model 2 or Model 4, simplified, 20. Model 2, tjTjical, 226. Model 4, typical, 227. Conorete Circuits : — {Con.) Switch machine: Motor connections. Model 2, 201. Motor connections. Model 4, 209. Pole changer. Model 2, 203. Pole changer, Model 4, 210. Symbols for, 354-359. Testing, for pick-up and drop- away of D. C. line relay, 276. Testing, for pick-up and drop- away of D. C. track relay, 276. Testing, for resistance of grounds, 372. Testing, for resistance of relay contacts, 276. Track: Alternating current, double rail, 273. Alternating current, single rail, 114-119. Written, 331-339. Circuit closers, bridge, 233, 234. Circuit controllers: Nomenclature for, 334-336. Switch (see switch circuit con- trollers) . Symbols for, R. S. A., 356-358. Circular measure, 388. Clearance diagrams: Model 2A dwarf signal and third rail, 244. Model 2 and Model 4 switch ma- chines, 214. Model 4 switch machine and third raU, 215. Clips, rail, 229. Closers, bridge circuit, 233. Common return or main common wire, 19, 22, 60, 70, 83, 93, 309. Concrete, Portland Cement: Box for measuring, 323. Cautions in use of, 322, 323. Consistency of, 321. Foundations (see foundations). Mixing by hand, 322. Mixing by machine, 322. Proportions of material for, 321. Specifications, R. S. A. for: Cement, 325. Consistency, 326. Density of ingredients, 326. Disposition, 327. Facing, 327. 422 INDEX Concrete CJoncrete : - — (Con.) Specifications, R. S. A. for: Finishing, 327. Forms, 326. Freezing weather, 328. General, 325. Gravel, 325. Measures, 325. Mixing, 326. Reinforced concrete, 328. Sand, 325. Stone, 325. Water, 325. Waterproofing, 328. Storing of, 321. Volumes of material for, 324. Controllers, circuit (see circuit con- trollers) . Control wire for signals, 22, 70, 83, 308. Control wire for switches, 19, 60, 308. Cooling tank (see tanks). Copper-clad wire tables, 307 (see also wire). Coppers for gravity primary battery, 291. Copper wire tables, 306, 307 (see also wire). Cross protection: Advantages of, 26. Apparatus for, 88-96. Circuit breaker, individual, 95. Circuit breaker, switchboard, 93. Circuits for, 88, 89. Description of, 24-26, 88-96. Operation of circuit breaker for, 91, 92. Polarized relays for, 92, 93. Principles of, 89. Safeguards, 93. Sectionalizing of plants for, 93, 94. Tests for, 94, 96. Uses of, 24-26. Cubic measure, 388. Cupboards, battery housing, 38, 1 58. Cycle of movements: Model 2 switch machine, 212. Model 4 switch machine, 213. Detector bars: Motion plates for, 229. Rail clips for, 229. Weights of layouts for, 365. Electro-pneumatic Development of electric interlock- ing, 6. Diagrams : Illuminated track, 105, 106. Track, 102, 103. Distances, shipping, between cities of U. S. and Canada, map of, 368. Direct current relays (see relays). Direct current generators (see gen- erators) . Dog chart, 55. Dry cell, 293, 294 (see also battery, primary) . Dry measure, 388. Dwarf signals (see signals mechan- isms). Dynamic indication: Advantages of, 16, 24. Circuits for, 20, 23, 61, 71, 73. Description of, 15, 21, 24, 60, 71, 74. Safety of, 24. * Uses of, 16, 21. Electric interlocking (see inter- locking) . Electric interlocking machines (see interlocking machine). Electric interlocking system, 15-28. Electric interlocking system (reprint from Catalogue No. 1 , Taylor Signal Co.), 405-413. Electric lighting, 127-130 (see also lighting) . Electric locking: Approach locking, 136. arcuits for, 134-139. Combination- of basic forms of, 138. 139. Definitions of, 133. Description of, 133-139. Development of, 133. Indication locking, 137, 138. Route locking, 135, 136. Screw release for, 134. Section locking, 134, 135. Sectional route locking, 135, 136. Stick locking, 137. Time release for, 134. Electric time release, 134. Electrolyte for storage batteries: Specific gravity of, 148. Weight of. 146. Electro-pneumatic interlocking, 5, 6. INDEX 423 Engines Engines, gasoline: Belting for, 373, 374. Cooling tank, connections for, 170, 171, 175. Cooling tank, location of, 171. Description of, 170-172. Dimensions of, 169. Foundations for, 169. Gasoline tank for, 171, 174, 175. Horse power of, 159, 169, 174. Illustrations of, 170. Installation data for, 169, 171, 174. Location of, 171. Specifications, R. S. A., for, 174, 175. Speed of, 169, 174. Starting, 171, 172. Stopping, 172. Tanks for, 170, 171, 174, 175. Troubles, 172-174. Cannot crank, 173. Carburetion, 172. Ignition, 172. Loss of compression, 172, 173. Loss of power, 173, 174. Mechanical difficulties, 173. Water connections for, 170. Estimates, information to be fur- nished by R. R., 413, 414. Fahrenheit temperatures compared with Centigrade, 393. First interlocking installation in U. S. A., 5. Fluxes for soldering and welding, 299. Foundations : Bracket post, 251. Concrete for (see concrete) . Gasoline engine, 169. • Ground signal mast, 252. Model 2 one arm dwarf signal, 253. Model 2 two arm dwarf signal, 253. Model 2A dwarf signal, 253. Model 3 dwarf signal, 253. Gasoline engines, 169-175 (see also engines) . Gasoline tanks (see tanks). Gears: Clearance of. Model 2A signal, 78. Formula for, 372. Speed of, 372. Indicating Generators, direct current: Capacity of, 159, 169. Charging circuits for, 163. Description of, 39, 162. Dimensions of, 169. Engines for driving, 159, 169. Failure to build up, 166. Fitting brushes to, 165. Foundation for, 169. General instructions for, 164, 165. Illustrations of, 39. Installation of, 162-169. Maintenance of, 163-166. Operation of, 162-164. Setting up, 162, 169. Shutting down, 164. Speed of, 169. Specifications, R, S. A. for, 166, 167. Starting, 162, 163. Symbols for, 359. Uses of, 39. Voltage of, 162. Weights of, 363. Gravity cell, 288-293 (see also bat- tery, primary) . Grounds, circuit for testing, 372. Hanger irons for transformers, 279. High Signals (see also signal mech- anisms) : Illustrations of, 17, 22, 25, 81. Masts for, 243. Spacing of arms for, 243. Symbols for, 348, 349. Weights of, 365, 366. Horse power of gasoline engines, 159, 169, 174. Hydrometer, Baume's, compared with specific gravities, 384. Hydro-pneumatic interlocking, 5. I Illuminated track diagrams, 105, 106. Impedance bonds: Description of, 120, 121. Dimensions of, 120, 121. Layouts for, 120, 121. Symbols for, 350. Weights of, 367. Incandescent lamps (see lamps). Indicating relays, alternating cur- rent (see relays). 424 INDEX Indication Indication, dynamic (see dynamic indication) . Indicadon locking. 137-139 (see also electric locking). Indication magnets: Energy' data for, IW. I!lustra*ions of, 51, 56. ResLsta- ce of, 194. Indication cdector, 58. Indicators: Alternating current: DjscriptiiHi of. Ill, 112. Dimenaons of, 270. Erergy data for. 271. Sy nbols for 354, 355. Weights of, l'«6, 367. Direct current: Battery capacity required for, 156, 157. Description of, i03-105. Dimensions of, 2o8. Energy data for, 265. 269. Illustrations of, 103-105. Resistance of, 265. 269 Symb:4s Tor, 354. 355. Uses of, 103-105. Wdghts of. 366. Individual return wire, 94. Installation data (see under name of apparatus) . Installation tools. 369. 370. InstrueticNis, installation and main- tenance (see under name of apparatus). Interlocking, introductory article on: Electnc. G. R. S. system of: Applicability of, 10-12. At what leverage b it economi- cal to install, 7. Average sales of G. It. S. plants, 11. Comparison of safety of, 9. 10. Cost of maintenance of, 8, 9. Developed by, 6. Distances functions may be operated from, 10. Effect of climatic conditions on, 10, 11. Exploited by, 6. Number of levers installed, 7. Ntimber of plants installed, 6, 7. Predietions as to future instal- lations of. 11. 12. Progress of. 6, 7. Proportion of plants installed which are G. R. S.. 6. 7. Interlocking Interlocking, introductory article on : — (Con.) Electric. G. R. S. system of: Reasons for adoption of, S-11. Safety of, 8, 11. ^ Size of installations of. 11. * Use in automatic territory of. 9. Use of track diagrams with. 11. WTiere used. 6. 7, 11. Electro-pneumatic : Installation, date of first. 5. 6. Installed at. first. 6. Plants installed, number of, 6. Hydro -pv.cuiiiii'Cc r Installation at, first, 5. Invention of, date of, 5. Plants installed, nimiber of, 5. 6. Mechanical: Class of maintainers for, 8. CV>mparison of safety of, 9, 10. Fust experimental installaticm in U. S. A., date of, 5. Installatioa in U. S. A., by, first, 5. Installation in U. S. .4., loca- tion of first, 5. Installation of, first important, 5. Invoitors of. 5. Latch locking, first use of. 5. Limitations of, 5. Origin of, 5. Patents, first granted. 5. Intoiocldng machine, electric : Acoeaaories for. 58, 59. Arrangements of beds for, 1^, 191. CatHnets. length of, 193, 191. Circuit breakers for, individual, 93-95. Oh;uits for, 88. Control of, 47-53. Description of, 47-59. Dimensions of, 186-131. Dog chart for, 55. Energy data for indication mag- nets, 194. Energy data for lei^er locks. 195. Features of. 47-49. Frame for, 53. Illustrations of, 18. 43, 48. 49. 52. Indication magnets, operating data for, 194. Indication selector for, 58. Individual circuit breakers for, 93-95. INDEX 425 Interlocking Interlocking machine, electric : — (Con.) Installation data for, 185-195. Lamp cases and number plates for, 57. Legs, number required and spac- ing, 190, 191. Length of, 190, 191. Lever, description of, 56, 57. Lever, illustration of, 51, 56. Lover lock for, 58, 195. Lever, operation of, 49-53. Ix)cking for, 53-56. Locking plates and locking, 53, 56. Maintenance of, 188, 189. Mechanical time release for, 58, 59. Notching, for lever locks, 192-194. Number of legs required for, 190, 191. Number plates for, 57 Operation of signal lever, 50, 53. Operation of switch lever, 49, 50. Polarized relay for, 57, 58, 92, 93. Resistance of indication magnets for, 194. Safeguards of, 47-49. Safety features of, 47-49. Shipment of, 185. Spacing of legs for, 190, 191. Storing of, 185. Terminal boards for, 57. Testing of, 94, 96, 188, 194. Time release for, 58, 59. Unit lever type, description of, 53-58. Uses of, 18, 19. Weights of, 363, 364. Wiring of, typical, 88. Interlocking stations: Arrangement of apparatus in, 33, Construction data, 35. Description of, 31-36. Diagrams of, 32, 34, 36. Illustrationa of, 31, 33, 35. Instal'ations, list of, 415, 416. Sizes of, 31. 33. Symbols for, 352. Joints in wire, 298-304. Junction boxes: Illustrations of, 316. Nails required for, 317. Symbols for, 351. Weights of, 367. Locking li Lamps, incandescent (see also lighting) . Ampere hoiys per signal, 155, 156. Arrangement for signal lighting, 128. Power required for, 127. Symbols for, 359. Types used in signal lighting, 127. Layouts : Detector bar, weights of, 365. Impedance bond, 120, 121. Switch, 218-225 (see also switch layouts) . Lead type storage batteries (see batteries, secondary). Levers : Cross connection wiring for double switch, 228. Double switch, wiring of, 228. Installed, list of, 415, 416. Notches for lever locks, 192-194. Signal : Description of, 50, 53, 56, 57. Operation of, 50, 53. Switch : Cross connection wiring for double, 228. Description of, 49, 50, 56, 57. Illustrations of, 51, 56. Operation of, 49, 50. Wiring of double lever, 228. Lever locks (see locks). Lighting, electric signal: Ampere hours required for, 155, 156. Bulbs for, 127, 128. Capacity of battery for, 155, 156. Economy effected, 127. Formula for, 156, 157. Lamps, incandescent, 127, 128. Power required for, 127, 155, 156. Precautions, 129. Recommendations for, 130. Reserve power for, 128, 129. Source of power for, 128, 129. When economical to use, 127. Lighting panels (see panels). Lightning arrester, 371. Limitation of mechanical inter- locking, 5. Linear measure, 388. Liquids : Measure of, 389. Specific gravity of, 385 Locking, check, 140, 141. 426 INDEX Locking Locking, electric (see electric lock- ing). Locking plates and locking, 53- 56 • Locking sheet, 54. Locks, lever: Application to lever, 192-194. Cutting of notches for, 192-194. Description of, 58. Dimensions of, 195. Energy data for, 195. Illustration of, 195. Installation data for, 192-195. Notching of levers for, 192-194. Specifications for, 192-194. Symbols for, 354. Test for clearance of, 193, 194. M Machines: Interlocking (see interlocking ma- chine) . Signal (see signal mechanism). Switch (see switch mechanism) . Magnets, indication (see indication magnets) . Main common or common return wire, 19, 22, 60, 70, 83, 93. 309. Maintenance (see under name of ap- paratus) . Maintenance tools, 369, 370. Manipulation charts, 102, 103. Map of shipping distances between cities of U. S. and Canada, 368. Masts, R. S. A. signal: Bracket, dimensions of, 243. Bridge, dimensions of, 243. Foundations for, 251, 252. Ground, dimensions of, 243. Measures and weights: French equivalents of, 390, 391 Metric, 390, 391. Tables of, 388, 389. Measuring box for concrete, 323. Mechanical interlocking (see inter- locking, mechanical). Mechanical time release, 58, 59. Mechanism : Signal (see signal mechanism). Switch (see switch mechanism) . Mercury arc rectifiers: Input for, 159. Voltage requirements of, 159. Motor Metals: Fluxes for soldering and welding, 299. Specific gravities of, 387. Weights of, 387. Metric measure system, 390, 391. Model 2A signal (see signal mech- anism) . Model 2 dwarf signal (see signal mechanisms) . Model 3 dwarf signal (see signal mechanisms) . Model 2 switch machine (see switch mechanisms) . Model 4 switch machine (see sAvitch mechanisms) . Motion plates, 229. Motors : Speed of, 168. Starting panels for, 181. Switch : Connection diagrams for, 201, 209. Cycle of movements of, 212, 213. Maintenance of, 206, 211. Symbols for, 359. Voltage for, operating, 159, 162. Motor generators: Employing A. C. motor: Floor space required, 159. Illustration of, 42. Input, 159. Symbols for, 359. Employing D. C. motor: Capacity of, 168. Description of, 39, 40. Dimensions of, 168. Failure to build up, 166. Fitting brushes to, 165. Floor space required for, 159, 168. General instructions for, 164, 165. Illustrations of, 40, 43. Input, 159. Installation data for, 162-168. Maintenance of, 163-166. Setting up, 162. Shutting down, 164. Speed of, 168. Starting of, 162, 163. Symbols for, 359. Weights of, 363. Motor starting panels, 181. INDEX 427 Nails N Nails: Amount required for junction boxes, 317. Amount required for trunking, 317. Sizes of, 382. Weights of, 382. Number plates, interlocking ma- chines, 57. Oiling diagrams: Dwarf bearing. Model 2A signal, 240. Mechanism, Model 2 A signal, 238. Operating data (see under name of apparatus) . Operating mechanisms (see under name of mechanism). Operating switchboards (see switch- board) . Paint: Amount required for trunking, 374. Application of, 374. Specifications, R. S. A. for, 374. Panels : Lighting : Dimensions of, 182. Switches for, 182. Weights of, 363. Motor-starting, 181. Pilot cell, 151 (see batteries, sec- ondary) . Pipe, wrought iron, dimensions of, 381. Piping for gasoline engine : Cooling tank, 170, 175. Gasoline tank, 171, 175, Running water, 170. Plan, track, 54. Plants, power, G. R. S. (see pov.cr plants) . Plates, motion, 229. Polarized relays: Description of, 57, 58, 92, 93. Functions of, 25, 92. Illustrations of, 58, 92, 186, 189. Pole changer: Model 2 switch machine: Adjustment of, 202-205. Connections for, 202, 203 R. S. A. Specification.s Pole changer: — (,Con.) Model 2 switch machine : Illustration of, 64. Installation data for, 202-205. Maintenance of, 206. Movement for, 202. Operation of, 63, 64. Testing of, 204, 205. Wiring for, 203. Model 4 switch machine: Description of, 68. Illustration of, 68. Maintenance of, 211. Operation of, 68. Wiring for, 210. Polyphase relays (see relays A. C). Posts, bracket: Foundation for, 25 i. Masts for, 243. Weights of, 365. Power interlocking (see interlock- ing). Power plants : Batteries for, 38, 39 (see also bat- teries) . Charging apparatus for, 39, 40 (see also charging apparatus) . Composition of, 37. Description of, 37-40. Illustrations of, 42, 43. Location of, 37. Switchboards for, 40-46 (see also switchboards) . Power switchboards (see switch- boards) . Primary batteries, 285-294 (see also batteries, primary) . Protection, cross (see cross protec- tion) . Pulleys, 372. Racks, battery, illustrations of, 37, 145. Rail clips, E. Z. motion plate type, 229. Rail sections, dimensions of, 375. R. S. A. specifications for: , Caustic soda primary cell, 287, 288. Concrete, 325-328. Copper for gra%nty cell, 291. Electric generator, 166, 167. Electric interlocking, extracts from : Painting, 374. 428 INDEX R. S. A. Specifications R. S. A. Specifications for: — (Con.) Electric interlocking, extracts from: Trunking, junction boxes and supports, 312, 313. Wire and wiring, 297-299. Gasoline engine, 174, 175. Lead type storage battery, 147- 154. Portland cement concrete, 325- 328. Principles of signal indications, 343. Signaling practice, 343-347. Symbols, 348-359. Voltage ranges, 282. Zinc for gravity cell, 293. R. S. A. standard apparatus: Battery chutes, 292. Battery jar, sand tray and cover, 146. Blades for upi>er quadrant signals, 249. Bracket p>ost masts, 243. Bridge signal masts, 243. Caustic soda primary cell, 286. Coppers for gravity battery, 291. Foundation for bracket post, 251. Foundation for ground signal mast, 252. Ground signal masts, 243. Spectacle, Design "A," 248,250. Spectacle, Design "B," 248. Zinc for gravity battery, 290. R. S. A. symbols: Cliarging apparatus, 359. Circuit controllers, 356-358. arcuit plans, 354-359. Instruments, 357-359. Location, 350-353. Relays, indicators and locks, 35-1, 355. Signals, 348, 349. Switches, derails, etc., 352, 353. Track plans, 348-353. Reactance bonds (see impedance bonds) . Relays : ^Alternating current: Boxes for, 274, 275. Description of, 109-113. Dimensions of, 270, 272. Energy- data for, 271, 273, 274 Illustrations of, 110, 112. Selection of, 109, 110. Types of, 110-112. Weights of, 366. Relays Relays: — (Con.) Boxes for: Dimensions of, 274, 275. Weights of, 367. Dimensions of, 266-272. Direct Current: Boxes for, 275. Dimensions of, 266, 268. Energy data for, 265, 267. Illustrations of, 100. 101. Resistance of, 265, 267. Testing of, 276. Weights of, 366. Energy- data for, 265-274. Indicating: Dimensions of, 270. Energy data for, 271. Weights of, 366. Model 1, D. C: Boxes for, 275. Energy data for, 265. Resistance of, 265. Test for pick-up and drop- away, 276. Test for resistance of contacts, 276. Weights of, 366. Model 2, Form A, Polyphase: Boxes for, 274. Description of, 110, 111. Dimensions of, 272. Energy data for, 271-274. Illustration of, 110. Test for resistance of contacts, 276. Weights of, 366. Model 2. FormB, A. C: Boxes for, 275. Description of. 111. Dimensions of, 270. Energy data for, 271. Illustration of, 112. Test for resistance of contacts, 276. Weights of, 366. Model 3, Form B, A. C: Boxes for, 275. Description of. 111, 112. Dimensions of, 270. Illustration of. 112. Test for resistance of contacts, 276. Weights of, 366. Model 9, D. C. : Boxes for, 275. Dimensions of, 266. Energy data for, 267. INDEX 429 Belays Relays: — (Con.) Model 9, D. C: Illustrations of, 101. Resistance of, 267. Test for pick-up and drop- away, 276. Test for resistance of contacts, 276. Weights of, 366. Model Z, Form B. A. C. : Boxes for, 275. Description of, 112. Dimensions of, 270. Energy data for, 271. Illustration of, 112. Test for resistance of contacts, 276. Weights of, 366. Motor, Three Position, D. C: Boxes for, 275. Description of, 98, 100, 101. Dimensions of, 268. Energy data for, 267, 268. Illustration of, 100. Test for resistance of contacts, 276. Weights of, 366. Polarized (see polarized relay). Symbols for, 354, 355. Testing: Pick-up and drop-away of, 276. Resistance of contacts for, 276. Three Position D. C. Motor (see Relay, Motor) : Relay boxes: Dimensions of, 274, 275. Symbols for, 351. Weights of, 367. Release, time (see time release) . Route locking, 135, 136 (see also electric locking). S Safeguards : Cross protection system, 24-26, 93. Dynamic indication, 24. G. R. S. system, 24-26. Interlocking machine, 47-49. Switch operating mechanisms, 61-63. Tests for cross protection, 94, 96. Safety of G. R. S. electric interlock- ing: Comparison with mechanical, 8. Cross protection, 89. Signals Safety of G. R. S. electric interlock- ing: — {Con.) Dynamic indication, 24. Features important to, 15. Test o*, 94, 96. Sand: Concrete, 325. Measuring box for, 323. Quantities of, for concrete, 324. Specific gravities of, 386. Weights of, 386. Screw release (see time release). Secondary . batteries (see batteries, secondary) . Sectionalizing of G. R. S. plants, 93, 94. Sectional route locking, 135, 136 (see also electric locking). Section locking, 134, 135 (see also electric locking). Selector, indication, 58. Semaphore spectacles (see specta- cles). Shipping distances between cities of U. S. and Canada, map of, 368. Shipping weights, 363-367 (see also weights) . Signaling practice: American, trend of, 11. Definitions of, 343-347. Principles of signal indications, 343. R. S. A. recommendations for, 343. Signals : Automatic block: Basis of adoption in America, 9. Percentage of American Rail- ways signaled, 9. Typ)e first used, 9. Blades for upper quadrant, 249. Bracket masts for, 243. Bridge masts for, 243. Control wire for, 22, 70, 83, 308. Dwarf (see signal mechanisms). Electric Ughting for, 127-130. Foundations for, 251-253. Ground masts for, 243. Illustrations of dwarf, 16, 74, 75, 83,86. Illustrations of high, 17, 22, 25, 81. Indications, principles of, 343. Interlocking (see signal mechan- isms). 430 INDEX Signals Signals: — (Con.) Mechanisms (see signal mechan- isms) . Spectacles for, 248. Symbols for, 348, 349. Weights of, 365, 366. Signal blades, 249. Signal lighting, 127-130 (see also lighting) . Signal mechanisms: Circuits for (see circuits, signal). Control wire for, 22, 70, 83, 308. Dwarf, solenoid (see solenoid dwarf signals) . Dynamic indication for (see dyna- mic indication). Foundations for, 251-253. Installation data: Adjustments, 237, 239, 241. Dimensions, 242, 245-247. Foundations for, 251-253. Lubrication of, 239. Masts for, 243. Method of taping wires to, 244. Storing of, 237. Spectacle adjustment for, 239. Tests of, 240. Maintenance of: Adjustments, 237, 241. Lubrication, 239, 241. Oiling diagrams, for, 238, 240. Spectacle adjustments for, 239. Tests for, 240. Masts for, 243 Model 2A non-automatic: Adjustment of, 237, 241. Circuits for, 23, 71, 254, 255. Clamp bearing for, 79. (Control of, 70-72. Control wire for, 22, 70, 308. Description of, 22-24, 77-79. Description of circuits for, 22-24. Dynamic indication, advan- tages of, 24. Dwarf bearing for, V9. Gears, clearance of, 78. Illustration of, 76. Installation of, 237. Length of control wire for, 308. Lever operation for, 50, 53. Lubrication of, 239. Maintenance of, 241. Method of taping wires to, 244. Names of parts for. 76. Oiling diagrams for, 238, 240. Operating data for, 241. Signals Signal Mechanisms: — (Con.) Model 2A, non-automatic : Simplified circuits for, 23. Size of control wire for, 308. Spectacle adjustment for, 239. Storing of, 237. Tests for, 240. Typical circuits for, 71, 254, 255. Weights of, 366. Model 2 A, semi-automatic: Adjustment of, 237, 241. Circuits for, 73, 256-259. Clamp bearing for, 79. Control of, 72-75. Control wire for, 22, 83, 308. Description of, 81, 82. Dimensions of, 242. Dwarf bearing for, 79 Dynamic indication advantages of, 24. Gears, clearance of, 78. Illustrations of, 80, 81. Indication spring attachment, 82. Installation of, 237. Length of control wire for, 308. Lever operation for, 50-53. Lubrication of, 239. Maintenance of, 241. Method of taping wires to, 244. Names of parts for, 80. Oiling diagram for, 238. Operating data for, 241. Size of control wire for, 308. Spectacle adjustment for, 239. Spring attachment, indication, 82. Storing of, 237. Tests for, 240. Typical circuits for, 73, 256- 259 Weights of, 386. Model 3, operating data for, 241. Model 7, operating data for, 241. Motor driven (see Model 2A sig- nals) . Operating and indicating circuits, description of, 22-26, 70-75. Solenoid dwarf (see solenoid dwarf) . Symbols for, 348, 349. Typical circuits for (see circuits). Types of. 70. Weights of, 365-366. INDEX 431 Single Rail Single rail A. C. track circuits, 114- 119 (see also track circuit A. C). Solenoid dwarf signals: Model 2: Circuits for, 84, 260, 261. Control of, 83, 84. Control wires for, 83, 308. Description of, 83-85. Dimensions of, 246, 247. Foundations for, 253. Illustration of, 83. Length of control wires for, 308. Names of parts for, 85. Operating data for, 241. Operating mechanism for, 85. Size of control wires for, 308. Weights of, 366. Model 3: Circuits for, 84, 262. Control of, 83, 84. Control wire for, 83, 308. Description of, 86, 87. Dimensions of, 247. Foundation for, 253. Illustration of, 86. Length of control wires for, 308. Names of parts for, 87. Operating data for, 241. Operating mechanism for, 87. Size of control wire for, 308. Weights of, 366. Soldering: Fluxes for, 299. Wire joints, 298, 303. Specific gravity of: Brick, etc., 386. Cement, etc., 386. Comparison with Baume's Hy- drometer, 384. Electrolyte, 143. Liquids, 385. Metals, 387. Sand, etc., 386. Stone, etc., 386. Wood, 385. Specifications (see under name of material) . Spectacles: Blades for, 249. Clamp bearing for, 79. Dimensions of, 248. Dwarf bearings for, 79. Torque curves for, 250. Square measure, table of, 388. Switch Stakes: Specifications for, 312, 313. Weights of, 367. Stations, interlocking, 31-35 (see also interlocking station). Stick locking, 137 (see also electric locking) . Stone: Concrete, size for, 325. Measuring box for, 323. Quantities for concrete, 324. Sizes for concrete, 325. Specific gravity of, 383. Weights of, 386. Storage batteries (see batteries, secondary) . Switches : Battery charging, description and circuits, 160, 161. Nomenclature of, 336. Panels for (see panels). Symbols for, 357, 358. Switchboards: Operating: Cross protection circuit breaker for, 90^-92. Description of, 45, 46. Dimensions of, 181. Illustrations of, 43, 44. Lighting panels for, 182. Location of, 37. Polarized relay for, 92, 93. Simplified circuits for, 45. Weights of, 363. Wiring for, 181. Power: Description of, 40-45. Dimensions of, 176-180. Illustrations of, 41-43. Location of, 37. Lighting panels for, 182. Manipulation of, 176-180. Simplified circuits for, 43. Starting panels for, 181. Weights of, 363. Wirings for, 176-180. Switch boxes (see switch circuit con- trollers) . Switch circuit controllers : Connections to switch point f or,232. Model 3, Form D: Dimensions of, 230. Illustrations of, 97. Weights of, 366. Model 4: Description of, 69. Illustrations of, 69. 432 INT)EX Switch Switch drcuit controllers: — (Con.) Moddo, Form A: Adjustable cam for, 231. Cam for. 231. Description of, 98. Dimensions of, 231. Illustrations of. 98, 99. Wd«hts of. 366. Symbols for, 357. Weights of, 366. Switch layouts: Modd 2 switch madiine: Double slip switch, 223. Hayes derail. 220. Movable point frt^. 224. Movable point frog with double slip switch. 225. Sngle slip switch, 222. Snele switch, 218. SUp switches, 222. 223. Split point derail. 219. Wrights of. 364. 365. Wharton or Morden derail, 221. Model 4 switch machine: Double slip switch, 223. Hayes derail, 22(X Movable point frt^, 224. Movable point frog with double slip switch, 225. Sngle slip switch, 222. Sngle switch, 218. SBp switches 222, 223. Split point derail, 219. Weights of. 364, 365. Wharton or Morden derail, 221. Switch machine: Model 2: Adjustment of, 201-204. Advantages of dynamic indica- tion of. 24. CSicuits for, 20, 61, 226, 228. Clearance compared with Model 4 switch machine, 214. Control of, 60. Control wire for, 19, 60, 308. Cross protection for, 24-26. Cycle of movements of, 212. Description of, 64-67. Description of circuits for, 19-22. Dim^iaons of, 216. Double lever for, wiring of, 228. Drilling of lock rod for, 205. Dynamic indication for, 21, 24, 60.67. Energy data for, 214. lUustrations of, 21, 62, 63. Switch Switch machine:' — (Con.) Model 2: Indication selector for, 58. Installation data for, 199-206. layouts for, 218-225. Length of control wire for, 308. Le\'er, illustrations of, 51, 56. Lever, operation of. 49, 50. Maintenance of. 199-206. Motor connections of. 291. Names of parts for. 65, 200. Of)erating data for. 214. Operation of. 60-67. Operation of controlling lev-er for, 49-50. Pole changer for, 64. Pole changer movement for, 202. Pole changer wiring for, 203. Safeguards of, 61-63. Simplified circuit for, 20. Size of control wire for, 308. Spring attachment for. 63. Storing of, 199. Switch circuit controllers for (see switch circuit control- lers). Testing of, 2ai. 205. Tie framing for, 19P. Time of operation ot, 22, 214. Tools for maintoiance of, 359, 370. Typical circuits for, 20, 61, 226, 228. Weights of. 365. Model 4. Adjustment of, 209. 210. Advantages of dynamic indica- tion of, 24. Circuits for, 20, 61. 227, 228. Clearance between third rail and, 215. Oearance compared with Model 2 switch machine, 214. Control of. 60. Control wire for, 19, 60, 308. Cross protection for, 24-26. Cycle of movements of, 213. Description of, 67-69. Description of circuits for, 19-22. Dimensions of, 217. Double lever for, wiring of, 228. Dynamic indication for, 21, 24, 60. Energy data for, 214. Dlustrations of, 16, 19, 67. INDEX 433 Switch Switch machine: — (Con.) Model 4: Indication selector for, 58. Installation data for, 207-211. Layouts for, 21'8-225. Length of control wire for, 308. I^ver, illvLstrations of, 51, 56. Lever, operation of, 49, 50. Maintenance of, 211. Motor connections of, 209. Names of part.s for, 66, 208. Operating data for, 214. Operation of, 67-69. Operation of controlling lever for, 49, 50. Pole changer for, 68. Pole changer wiring for, 210. Safeguards of, 61-63. Simplified circuit for, 20. Size of control wire for, 308. Storing of, 207. Switch circuit controllers for, 69. Testing of, 210, 211. Third rail clearance for, 215. Tie framing for, 207. Time for operation of, 214. Tools for maintenance of, 369, 370. Typical circuits for, 20, 61, 227, 228. Weights of, 365. Symbols for, 3.50. Switch mechanisms (see switch ma- chine) . Switch operating mechanisms (see switch machine). Symbols : Lever contacts. Model 2 inter- locking machine 336. R. S. A. standard: Charging apparatus, 359. Circuit controllers, 356-358. Circuit plans, 354-359. Instruments, 357-359. Location, 350-353. Relays, indicators and locks, 354, 355. Signals, 348, 349. Switches, derails, etc., 352, 353. Track plans, 348-353. Tables (see vmder name of material) . Tanks: CooUng, for gasoline engine: Capacity of, 174. Track Tanks: — (Con.) Cooling for ga.soline engine: Dimensions of, 174. Location of, 171. Specifications, R. S. A., for, 174, 175. Water connections for, 170. Gasoline: Capacity of, 174. Dimensions of, 174. Location of, 171. Specifications, R. S. A., for, 174-175. Taylor (G. R. S.) electric interlock- ing system (reprint), 405- 413. Temperature : Comparison of Fahrenheit and Centigrade scales, 392, 393. Effect on G. R. S. electric plants, 10, 11. Effect on mechanical plants, 10, 11. Terminal boards: Interlocking machine, 57. Transformer, 122, 123. Tests (see under name of apparatus) . Thermometer scales: Comparison of Fahrenheit and Centigrade, 392, 393. Threads, U. S. standard screw, 380. Tie framing: Model 2 switch machine, 199. Model 4 switch machine, 207. Time release: Electrical, 133, 134. Mechanical, 58, 59. Symbols for, 358. Tools, maintenance, 369-370. Towers (see interlocking stations). Track circuits: Alternating current, double rail: Bonds for, 120, 121. Diagram of, 273. Energy curves for, 273. Impedance bonds for, 120, 121 Relays for (see relays A. C). Transformers for (see trans- formers) . Alternating current, single rail: Advantages of, 114. Central energy scheme, 117- 119. Description of, 114-119. Diagrams of, 116, 117. Energy required for, 115. 434 INDEX Track Track circuits: — (Con.) Alternating current, single rail: Illustration of, 118. Limitations of, 114, 115. Relays for (see relays A. C). Transformers for (see trans- formers) . Types of, 116, 117. Direct current: Batteries for (see battery, primary). Bond wires for, 378. Boot leg for, 316. Channel pins for, 378. Indicators for, 103-106 (see also indicators) . Locking circuits for (see electric and check locking). Relays for (see relays, D. C). Tests for, relays, 276. Tools for, 370. Wire sizes for, 297. Track diagrams, 102-106. Track indicators: Alternating current: Description of, 111-113. Dimensions of, 270. Energy data for, 271. Weights of, 366, 367. Direct current: Description of, 103-105. Dimensions of, 268. Energy data for, 265, 269. Illustrations of, 103-105. Weights of, 366. Track plans: Dog chart for, 55. Illustrations of, 54. Locking sheet for, 54. Symbols for, 348-353. Track tools, list of, 370. Track transformers (see trans- formers) . Transformers : High tension line: Capacity of, 280, 281. Combinations of, 122, 123. Description of, 122, 123. Dimensions of, 279. Hanger irons for, 279. Illustrations of, 122. Ratings ^f, 280, 281. Terminal board for, 122. Weights of, 363. Windings for, 122, 123. Weight Transformers : — (Con.) Secondary track: Description of, 123, 124. Dimensions of, 282. Illustration of, 123. Rating of, 282. Weight of, 363 Windings for, 123. Symbols for, 359. Trunking: Area of groove in, 314. Board feet for, 315. Bootleg for, 316. Capacity of, 314. Capping for, 315. Construction of, 312, 316. Dimensions of, 315. Hooks required for, 317. Joints in, 312, 315. Junction box for, 313, 316. Nails required for, 317- Paint required for, 374. Screws required for, 317. Sections of, 315. Specifications for, 312, 313. Stakes for, 312, 313. Supports for, 312, 313. Surfacing of, 315. Table for determining size of, 314. Weights of, 367. W Weight: Avoirdupois, 388. Brick, etc., 386. Cement, etc., 386. Electrolyte, 146. Lag screws, 382. Metals, 387. Nails, 382. Pipe, 381. Sand, etc., 384. Shipping: Battery chutes, 367. Bracket posts, 365. Cantilever bracket, 366. Charging apparatus, 363. Detector bar layouts, 365. Dummy mast, 366. Dwarf signals, 366. Fixed arm, 366. Generators, 363. Impedance bonds, 367. Indicating relays, 366. Indicator groups, 366. Indicators, 366, 367. INDEX 435 Weight Weight : — (Con.) Shipping: Interlocking machines, 363, 364. Junction boxes, 367. Lever lock, 364. Lighting panels, 363. Locking, 364. Motor generators, 363. Posts for relay boxes, 367 Relay boxes, 367. Relays, 366. Signals, complete, 365, 366. Signals, dwarf, 366. Signals mechanism, Model 2A, 366. Stak&s, 367. Switchboards, 363. Switch circuit controllers, 366. Switch circuit controller rods, 366. Switch layouts. 364, 365. Switch machines, 365. Transformers, 363. Trunking. 367. otone, etc., 386. Storage battery cells, 146. Tables of, 388, 389. Water, 389. Wire, 306, 307. Wood, 385. Welding, fluxes for, 299. Wire: Aluminum compared with copper, 310. Common return, 19, 22, 60, 70, 83, 93, 309. Control for signals, 22, 70, 83, 308. Control for switches, 19, 60, 308. Copper (see also rubber-covered) : Carrying capacity of, 310. Compared with aluminum, 310. Fluxes for soldering, 299, Gauge for, 305. Hard drawn, table of, 307. Interlocking specifications, R. S. A., 297-299. Joints in, 298-304. Soft drawn, table of, 306. Soldering of, 303. Splicing of, 298-304. Taping of, 303, 304. Zinc Wire:— (Con.) Copper-clad, table of, 307. Gauges for, 305. Individual return, 94. Iron, table of, 306. Rubber-covered copper: Conduit for, size of, 314. Interlocking specifications, R. S. A., 297-299. Joints, 298-304. Manufacturer's Engineers' standard, dimensions of, 311. R. S. A. standard, dimensions of, 311. Soldering of, 304. Splicing of, 298-304. Tags for, 299. Taping of, 303, 304. Trunking for, size of, 314. St«el, table of, 306. • Symbols for, 359. Weights of, 306, 307. Wirings (see circuits, also name of apparatus) . Wood, specific gravity and weight of, 385. Written circuits: Description of, 331, 332. Nomenclature of: Circuits, 334-336. Circuit controllers, 334-336. Indicator contacts! 335. Knife switch, 336. Latch contact, 336. Lever contacts, numbering of 336. Operated units, 332-334. Push button, 336. Relay contacts, 335. Terminals, 336. Time release contacts, 335. Wires, 337, 338. Illustrations of, 338, 339. Plans involved, 331, 332. Use of, 331. Wrought iron pipe: Dimensions of, 381. Weight of, 381. Zinc for gravity battery cell, 290. LJ