II Class _nUill3J Bnnk ' V/o, CDPXRIGHT DEPOSm CUTTING CENTRAL STATION COSTS CUTTING CENTRAL STATION COSTS Ways by tv/iic/i Central Station Majiagei^s, Operating Engineers and Sales Managers are Meeting High Costs Compiled by S. B. WILLIAMS Commercial Editor, Electrical World First Edition PUBLISHED BY ELECTRICAL WORLD McGRAW-HILL BOOK COMPANY, Inc. Sole Selling Agents 239 WEST 39th STREET, NEW YORK 1919 Copyright, 1919, by the McGRAW-HILL COMPANY, Inc. \v^ .^0 fiPR 23 19)9 (7bci.A51?5l01 PREFACE Central stations during the great war met the problems of fur- nishing energy under heavj^ restrictions. War brought the ne- cessity of producing power with poor fuels, higher labor costs and extraordinary conditions of demand in many localities. The central station manager produces electricity to sell. He has always been aggressive in producing power at lower costs and the war has acted as an added incentive to make useful every pound of coal, every piece of machinery and equipment and every dollar of administrative and selling expense. Practical methods by which scores of central station men the country over have worked out their problems have been compiled in this book. The material has appeared in the Electrical World during the last nine months of war. In many cases, one man's idea in one issue has suggested to some other man his plan, which in subsequent issues has been presented for the industry. The industry now is entering a period of reconstruction and many of the plans and methods which have proved successful have a direct application in the everyday practice of the central station manager. To make this material most easil}^ available to the reader, the book has been divided into sections — taking up in order operat- ing economies in boiler and generating rooms, line construction and distribution methods and substation practice, then commer- cial practice and administrative plans, including tried out meth- ods of reducing costs of meter reading, billing collections, the discontinuance of free service and the financing of extensions. The book concludes with timely articles on the training of women in central station work. This book is essentially a collection of methods. It is pre- sented as a practical help to the men in responsible charge of central station work — a convention on paper to help solve every- day problems. CONTENTS fAGE Preface v Section 1 The Boiler and Engine Rooms 1 Section 2 The System 104 Section 3 The Shop . 196 Section 4 JMeter Reading, Billing and Bill Delivery, AND Collections . 201 Section 5 Commercial Department 240 Section 6 Management 271 Section 7 Female Labor 300 Index 314 CUTTING CENTRAL STATION COSTS SECTION I THE BOILER AND ENGINE ROOMS INCREASING PLANT EFFICIENCY Higher boiler pressures, higher temperatures of superheat, higher vacua, the use of powdered coal, the installation of boiler efficiency instruments and the introduction of bonus systems are six means which an operating engineer in the Middle West considers as most likely to produce important coal savings. Boiler pressures higher than the standard are considered the most important source of saving. While the general impression now is that no saving can be made by going to higher pressures on account of the high cost of the equipment, it is the belief of some engineers that when development charges have been some- what reduced it will be possible to make high-pressure equipment at less cost than apparatus for 200 lb. (14 kg.) pressure. This opinion is based upon the belief that the boilers for higher pressures will contain smaller tubes, which will give more area with the use of less metal. While the theoretical saving which can be made by the use of higher superheat is small, the actual saving is really greater than the theoretical saving, owing to the fact that the elimination of moisture from the steam through- out a large part of the duty cycle of the steam very largely re- duces friction losses. As is well known, many experimenters are working on the problem of powdered coal, and although a number of attempts have been made to promote fraudulent 2 CUTTING CENTRAL STATION COSTS schemes in this field, a real and legitimate work is being done. Sooner or later it will bring about successful means to release for active work more of the heat units in coal. The saving which can be made through the use of higher vacua is probably one that demands attention in every plant at the present time. All operators do not thoroughly realize that an increase in the vacuum from 28 in. to 29 in. (71 cm. to 74 cm.) effects a 4 per cent saving on the coal pile, the engineer re- ferred to says. It is usually practicable to make such an in- crease, although it sometimes entails the installation of better air-pump equipment. Installing boiler-room efficiency instru- ments and adopting bonus systems should be considered to- gether. They assume increased importance daily as the shortage of power-plant labor becomes more apparent. It is altogether possible that the tendency of the current year will be to employ more intelligent help for the boiler room, even to the partial neglect of the turbine room, so that the investment in boiler- room efficiency instruments and the bonus-paid employees may be capitalized to the fullest extent. PRACTICAL SUGGESTIONS FOR ECONOMY IN USE OF FUEL An interesting contribution on the subject of the burning of lower-grade fuels without greatly increasing the boiler-room investment is made by P. B. Juhnke, chief load dispatcher of the Commonwealth Edison Company of Chicago. The steaming value of a given coal is within certain well- defined limits a function of the size of the coal; likewise, the price of coal is dependent on the size selected, screenings being rated lowest in value. While their test B.t.u. value may be equivalent to that of any given coal, their steaming value in boiler rooms is considerably lower than similar screened coal. However, as screenings will always be a necessary by-product in the coal industry and as 90 per cent of the time they are sufficient, they constitute the logical fuel for central stations. Burning the lower grade of fuel exclusively, however, requires additional boiler-room equipment over what would be required with the more expensive screened coal for a given steaming capacity. The additional investment required is vitally impor- THE BOILER AND ENGINE ROOMS 3 tant to central-station companies, whose loads have the familiar sharp peaks, during which time alone the development of max- imum capacity is necessary. A decided step in the direction of economy of both boiler- room investment and hig'h-jzrade fuel has been made bj" the Com- monwealth Edison Company in its principal ^^oneratino: stations during several peak seasons. The fuel ordinarily burned is not quite sufficient for the development of maximum capacity during the winter evening peaks, and is supplemented in these periods by higher-grade fuel, to permit maximum output. This is done by storing the more suitable coal on the floor and during the peak supplementing the stoker firing of lower-grade fuel by hand firing of the higher-grade fuel in the proportion of approximately fifty-fift3\ Such practice permits good combustion of the entire supply and enables the stations to carry their rated full load and more at the most critical time of the daily load, something that would be scarcely possible were the hand firing of high- grade coal not resorted to. This scheme of developing full load, however, is not altogether free of objections. First, it requires that a large amount of coal be stored on the boiler-room floor, a poor place for coal according to modern conceptions. Second, it requires a large amount of help to store and shovel the coal into the stoker, and this help may be difficult to obtain and is quite expensive. To overcome these difficulties a scheme has been adopted at the Eisk Street station which has proved quite satisfactory. High- grade coal is kept in one bunker out of every group of sixteen, and the corresponding boiler is kept banked at all times except during peak loads. A traveling bucket movable by a crane is filled from this bunker to supply high-grade fuel to any other hopper requiring it. This arrangement has reduced the labor expense considerably. Despite the aforesaid difficulties connected with this method of supplementing low-grade with high-grade coal when required, the underlying principle seems good enough to demand special consideration from designers who look to the fuel situation ahead. Provision for auxiliary high-grade coal bunkers that will be large enough to meet the increased demands during peak periods has been made in a few stations, but it might be advisable for all future stations. The capacities of such bunkers need hardly 4 CUTTING CENTRAL STATION COSTS exceed 5 per cent to 10 per cent of the ordinary bunker capacity. Perhaps one or more central bunkers with chutes to a number of stokers would be desirable, but the method of storing and dis- tributing the coal is mosth^ a matter of detail arrangement. It is not difficult to imagine conditions which will give addi- tional economic importance to providing auxiliary bunkers for peak coal, conditions which will affect operating costs as well as investment cost. When they obtain, such an arrangement will recommend itself still more forcibly and is likely to show a de- cided saving both in the outlay for investment and in operating costs. To state offhand the saving effected in dollars and cents is somewhat difficult, as location, the price of coal, cost of boiler equipment, and the like, are factors entering into the matter. Outside of the auxiliary coal bunkers, very few other changes will be necessary to adjust the fuel to the load conditions. AVith such an arrangement one precaution would have to be taken — to prevent waste of the higher grade coal, it being much easier to burn. With hand firing the difficulties connected with burning the higher-grade fuel serve as a good brake against this tendency in human beings to make things as easy for themselves as possible. But even at the worst it would not be a grievous problem for modern types of generating-station executives to solve. EXPERIENCE WITH PULVERIZED COAL In an effort to determine the advisability of utilizing pulver- ized fuel in its plants, the Milwaukee Electric Railway & Light Company early in 1918 decided upon a trial installation at the Oneida Street station. The necessary equipment for preparing and feeding the coal was installed and the boiler was placed in service during the early part of May. From that time until early in August, when the installation was finally proved successful, changes were made to eliminate undesirable conditions encoun- tered during preliminary operation. Drying and Pulverizing Equipment. The drying and pul- verizing equipment, installed in a room near the plant coal bunkers, consists of one 15-ton-per-hour indirect-fired dryer and one 4-ton-per-hour pulverizer. From one of the coal bunkers the fuel as delivered to the plant is carried to the drj^er supply THE BOILER AND ENGINE ROOMS 5 bin by means of a screw conveyor and bucket elevator. From this supply bin the coal is drawn into the drying cylinder by means of another screw. It is carried through the dryer by means of gravity and discharged into an elevator which carries the dried fuel to the pulverizer supply bin. In the dryer the moisture is reduced from 11 per cent to 1 per cent at the rate of about 10 tons per hour. In passing to the pulverizer supply bin the coal is run over a magnetic separator pulley which removes such iron and steel as has been carried that far. From the bin last mentioned the fuel is fed to the pulverizer through a small screw conveyor on top of the mill. Being driven from the mill shaft by means of a small belt, this screw can be varied in speed through a cone pulley arrangement to allow for the kind of material being powdered. After passing through the pulverizer the fuel is carried by means of a screw conveyor to the pulverized-fuel storage bin in front of the boiler. All drives on the conveying and pulverizing equipment are so arranged that only such machinery as is in use will be operating. The equipment for firing the fuel into the furnace consists of a blower and two screws driven by variable-speed motors. The screws, at the base of the powdered coal bin, carry the coal at a uniform rate to the feeder pipes, where it is thoroughly mixed with air by means of agitator wheels attached to the end of the screw shafts. From the paddlewheel the fuel is carried into the furnace by the air blast supplied from the blower. The furnace is of the Dutch-oven type so as to insure the proper flame travel, thus preventing destruction to the brickwork. When the boiler was first put into operation a number of unde- sirable conditions resulted. An insufficient air supply caused high furnace temperatures. These temperatures caused fusion of the ash particles and a consequent accumulation of slag be- tween the tubes, on the furnace walls and in the ash pit. The removal of the molten slag presented a rather difficult proposi- tion. It was also found that the combustion chamber was of in- sufficient size. High gas velocities resulting from insufficient air tended toward destruction of the refractor^^ surfaces of the fur- nace. A new furnace was therefore designed. The combustion chamber was enlarged, and a regulated air supply was provided 6 CUTTING CENTRAL STATION COSTS for by means of a number of auxiliary air openings equipped with dampers. The accumulation of slag in the pit was pre- vented by raising the point of admission of the fuel into the furnace. As a result the flame path was raised above the base of the pit; hence particles of ash dropping from the flame are not fused. The ash can therefore be drawn from the pit in the form of a powder and small slugs of slag. Analysis has shown that the ash contains practically no carbon. Having established satisfactory furnace operating conditions, a series of efficiency and capacity tests were conducted to prove contract guarantees. The brickwork was then given a thorough trial by carrying the boiler at a continuous rating of 180 per cent over a period of several days. A final efficiency test follows : Log of Official Test at Oneida Street Station Heating surface, sq. ft 4,685 Temperature of feed water (deg. Fahr.), average 157.2 Temperature of steam (deg. Fahr.) , average 448.7 Temperature of flue gases (deg. Fahr.) , average 495.3 Average boiler pressure 167.0 Fuel (100 per cent bituminous coal) fired per hour, lb 1990.6 Water apparently evaporated per hour lb 16,392.0 Water apparently evaporated per lb. of coal, lb 8.23 Factor of evaporation 1.1502 Water evaporated from and at 212 deg. Fahr., per lb. of coal, lb. 9.47 COo, per cent average 13.85 O, per cent average 4.38 CO None Average, Fuel Analyses : Per Cent Moisture 10.49 Volatile 35.96 Fixed carbon 49.53 Ash 15.93 Sulphur 2.04 B.t.u., as received 10,779 B.t.u., dry 12,045 Accumulation of slag on tubes None Condition of smoke Light Heat effect on brick None Backlash of flame in burner None Lb. steam per hour 16,390.3 Lb. steam per hour from and at 212 deg. Fahr 18,842.6 Per cent of rating 116.7 Boiler efficiency 85.22 (Flues blown five times during test.) Fuel Preparation Deductions: Coal used in dryer, lb 1,140 THE BOILER AND ENGINE ROOMS 7 Kilowatt-hour motor operation (449.3), coal equivalent at 3 lb. per kw.-hr 1,348 Total deduction, lb 2,488 Resultinfic net efficiency (per cent) 81 No deduction made for stand-by losses in dryer. The boiler is an Edge Moor three-pass water-tube boiler, equipped with a superheater and vertical baffles. The coal feeders and burners are of the "Lopulco" type, manufactured by the Locomotive Pulverized Fuel Company of New York. Because of the nature of the equipment the coal could not be weighed on the firing floor. To arrive at exact coal figures, it was necessary to run all drying and pulverizing equipment free of coal. The fuel in the pulverized storage bin was run to as low a level as possible and a measurement taken to determine the cubical contents of the powdered coal on hand at the start. Coal for the test run was then weighed into the system at the moist coal bunker. At the close of the run the starting conditions so far as was possible were again established. The samples for analysis, upon which the test results are based, were taken at the moist coal bunker as the coal was weighed in. Moisture samples were also taken at the pulverizer feeder and the burners. All analyses were made at the laboratories of the Milwaukee com- pany. The feed water used during the test was weighed on the stand- ard tank scales of 2000 lb. (907 kg.) capacity each. All feed- pump gland leakage was accounted for in the way usually adopted on standard boiler tests. All temperatures and pressures were taken with instruments which previous to the test had been checked against standard instruments. The blow-off piping on the boiler was disconnected so as to insure against any possible loss of water. Flues were blown five times during the twenty-four hours. Flue gas analyses were determined by means of an Orsat apparatus. Throughout the test very uniform conditions were maintained. The speed of coal feeders and the drafts carried were held con- stant. The feed-pump speed had to vary somewhat from time to time. The variation in the rate of evaporation was, however, due to slight changes in the quality of coal during the test run. Pulverized Coal Versus Mechanical Stokers. 1. Under this 8 CUTTING CENTRAL STATION COSTS heading fuel-preparation costs will be considered first. In the case of powdered coal this information can be classed under three general divisions : (a) The cost of crushing the coal. This expense is the same for both types of equipment. (b) The cost of drying and pulverizing the coal. Although no cost records are available at present, it is estimated that 32 cents per ton will cover this preparation cost in a 200-ton-per- twenty-four-hour plant using bituminous coal containing about 12 per cent moisture. (c) The maintenance cost of the drying and pulverizing plant. This unit has not been determined from actual experience ; how- ever, it is estimated that 3 cents per ton will cover the mainte- nance. In stoker practice the maintenance cost per ton of fuel fired is close to 5 cents. Summarizing the above facts, it is evident that, with fuel at $5 per ton, the gross efficiency shown by the pulverized-fuel boilers will have to exceed that shown by the mechanical-stoker-fired boilers by 6 per cent in order to offset coal preparation costs. A 6 per cent deduction from a gross efficiency of 85 per cent gives a net efficiency of 79 per cent for the powdered coal burner. In stoker practice the maximum attainable gross efficiency at any of the Milwaukee electric plants has been 80.54 per cent. Deduct- ing 2.5 per cent for auxiliary uses, the resulting net efficiency is 78 per cent, which is lower by 1.1 per cent than the figure ob- tained in pulverized-fuel practice. Other advantages resulting from the use of pulverized fuel are summarized herewith : 2. Continuous boiler operation at a uniform rating as well as a constant efficiency is made possible. At no time is there a loss in capacity due to the clinkering of coal on the grates or the cleaning of fires. 3. Heavy overloads can be taken on or dropped off in a very brief time through adjustment of the coal feeders and the fur- nace drafts. 4. From 97 to 98 per cent of the combustible in the coal is utilized, regardless of the quality of the fuel. 5. The ash-handling costs are reduced to a minimum owing to the reduced volume. 6. The banking conditions when operating with pulverized fuel THE BOILER AND ENGINE ROOMS 9 are somewhat different from those obtained in stoker practice. By stopping the fuel supply and closing up all dampers and aux- iliary air inlets a boiler can be held up to pressure for about ten hours. The furnace brickwork, having been heated to incandes- cence during operation, gives off radiant heat which is absorbed by the boiler rather than sent out through the stack. The ease of controlling the fuel, feed and drafts, the ability to take on heavy overloads in a brief time, the thorough combus- tion of the coal and the uniform high efficiency obtainable under normal operation make pulverized coal a most satisfactory form of fuel for central-station uses. The full story of maintenance expense is only partly known as yet; but indications are that no unusual difficulties will be met. The cost of fuel preparation and labor for operating a boiler room fully equipped with pulverized-coal-burning boilers will be a question for the engineer to decide for himself according to his particular conditions. Properly installed with respect to capacity of storage, size of dryer and pulverizers, and on a suffi- cient number of boilers properly and fully to employ the mini- mum number of men, the pulverized-fuel installation will most undoubtedly be more advantageous. The chief items that must be borne in mind by engineers are the ease with which a high efficiency is obtained and the constant nature of that efficiency as compared with the absence of these advantages in a stoker-fired boiler, unless very closely supervised. There is no doubt that wdth a well-equipped plant burning pul- verized fuel having all the necessary recording and indicating instruments to guide the operators in maintaining the proper conditions, a low^er cost of generating steam will be possible than has heretofore been the case wdth any other style of equipment. BURNING DUST-BEARING COAL Several interesting observations on the flow of air through coals w^ere made by L. A. Stenger which have a direct beaming on the important question of fuel conservation in this country. Preliminary tests showed that the weight of air passing through a given coal per unit of time is dependent upon the difference in air pressure through the bed, thickness and area of the bed, state of surface wetness of the coal, and most important, the degree of 10 CUTTING CENTRAL STATION COSTS fineness of the coal particles. These tests were made with a sim- ple apparatus like a gasometer, which would deliver a volume of air at constant pressure through a cup with screened bottom, which contained the coal under test. The time taken to force the known volume of air through the coal was measured with a stop watch. This furnished data to compute unit air flow. ^ Different coals of various screen gradings, dust contents, con- ditions of surface wetness, etc., were tested under comparative conditions. Tests comparing surface, dry, dust-bearing coal with the same coal when the surface was wetted throughout the mass showed that the wet coal allowed approximately twice the air flow that the dry coal would. This is due to the fact that the water collects the small grains, holding them together and to the larger pieces, thus preventing their settling and filling the void spaces. After the coal is again dried, if it is not agitated too much, the dust is cemented together loosely by the deposited soluble salts of the coal. The resulting increase of air fiow ex- plains the improvement in combustion of wetted coal. It was DU ' 1 1 II 9 20-MESH SCREEN 40 1 1 w50 c Figures on Curve Indicate Diameter of Hole of Screen on which Coal is held V 10 20 Seconds represent Time rr\^os\jrQd on Gasometer \ 10 \ ON BO-MESH SCREEN \ //A ICH O LB 5 SEC r- - n ^-<1 0.1 -e^b 0.25 0.5 ^ _ ^ «w 0.2i prt 100 200 500 i r K Boi ler C (lOOP o / 4 / y /o i ^^ < 1 o/\ / to o too O to Q cu o o tn OJ o o — o ocu o o o o cu" British Thermal Unit of Coals as Fired uX70 goe?5 ^•Heo T5 to C « utaa ^ ^ U- t-^^ ^^ "*^ » ' 0^ '^ oVoughiogheny Coal • 1 llinois Cool • • 100 eoo c2 eOO 300 400 500 Air Flow Through. Coals ,, Lb. per Hour per Square Foot, 6"Coa1 Thickness, 0.5 Pressure Figs. 3 and 4 — ^Relation of Measured Aie Flow to Boiler Performance as ordinarily fired and that there is an important relation be- tween that property of fuels and boiler and furnace performance. Losses in efficiency due to dust in coal are traced to the diffi- culty in maintaining a free-burning, uniform fuel bed. Holes, ridges or streaks will form. Air passing through holes and areas of burned-out ash causes augmented chimney losses. Areas of coal impermeable to air lie inert, are only coked, not burned, and finally contribute to losses in the ash pit. Boiler capacity is lim- THE BOILER AND ENGINE ROOMS 13 ited, owing to low efficiencies and to reduced rates of combustion. A study of the data presented herewith and other experiences with dust-bearing coals on different types of stokers, including forced-draft stokers and hand-fired furnaces, shows that it is impossible to attain as good results as may be had from dust- free coals of lesser B.t.u. values. There is not much hope that the operating boiler efficiencies ordinarily obtained in large plants can be raised and maintained at any desirable standard if dust-bearing coals are burned with ordinary furnace equip- ment. To add to the trouble fuel is becoming poorer in all re- spects and more expensive. Limitation of boiler capacity also contributes to low plant efficiency. This leads to higher costs, both of boiler-house equipment and of operation. Although good types of forced-draft stokers with the ability to increase steam output to 250 or 300 per cent of boiler rating aid much in this regard, their operating efficiency is lowered by dust-bearing fuels. ^ A plan for permanently raising operating boiler efficiency and the boiler capacity of a steam-power plant follows : Crush all coal, if necessary, so the largest lumps will not be over 1 in. (2.54 cm.) in size. Screen on a mesh chosen to remove all dust of %-in. (3.175-mm.) size and less. Dry and pulverize the dust and burn in pulverized coal-burning furnaces serving a part of the present boiler installation. The coarse coal may be burned in the remaining furnaces, in which no changes have been made. The data in the table give comparative estimates on the plan, based on these assumptions : 9600 B.t.u. and 13 per cent mois- ture in coal as bought ; 25 per cent of the dust is screened from coal (dust having 8600 B.t.u. and 15 per cent moisture or 10,000 B.t.u. and 1 per cent moisture as fired) ; 40 cents per ton of dry dust is the approximate cost of screening all coal and drying and pulverizing the dust, or 9 cents per ton of coal bought. These costs are based on 1917 prices of a pulverizing plant of about iThe "operating boiler efficiency", e= (100 — a) X & X Present Pulver- Plant Opera- Coarse ized Aver- tion Coal Coal age 55 72 76 73 9600 9900 10,000 9922 Operating boiler efficiency (per cent) . . Calorific value of coal as fired (B.t.u.) Lb. coal as fired per 1000 lb. water evap- orated 184 134 Lb. coal as bought per 1000 lb. water evaporated .... 139 Lb. coal as required per 1000 lb. water evaporated (includes coal for drying dust) , total 184 140 Lb. coal saved .... 44 Coal saved ( per cent ) .... 24 Added cost of coal per ton brought due to treatment $0.09 Net financial saving (per cent) with coal costing : $1 per ton at plant .... 13.2 $2 per ton at plant .... 19.7 $3 per ton at plant .... 21.2 Approximate increase in boiler rating, from 125 to 175 per cent of rating (per cent) 40.0 It may be seen that the net saving is based upon the possible increase in boiler operating efficiency only. A further saving is possible in plants with the usual load factor of lighting and power plants by bringing about a decrease of the quantity a in the plant efficiency formula given in the footnote (page 13). This was not estimated on account of the indefiniteness of the figures involved. It would be no inconsiderable economy, owing to less banking of fires, as a smaller number of boilers would have to be fired to carry the peak load than under the conditions previously existing. "With the suggested plan in operation the boiler plant could be better controlled and it would be more flexible and more reliable. There would be much less ash to dispose of. The savings brought THE BOILER AND ENGINE ROOMS 15 about in money, coal and transportation and the inexpensive in- crease of power capacity as compared witii the previous output would be very helpful at any time. HIGH-GRADE COAL FIRED DURING PEAK Influx of war industries coupled with slow deliveries of equip- ment made the problem of carrying the 1917-18 winter's peak a difficult one for the Moline plant of the Moline-Rock Island Manufacturing Company, which supplies electric service to the * ' Tri-Cities, " Davenport, Rock Island and Moline. Boiler ca- pacity appeared to be the limiting factor. In order, therefore, to obtain the maximum rating out of the existing equipment only high-grade coal was burned during peak hours. Under ordinary conditions Iowa coal was burned. Getting the high-grade fuel on the fires at the critical time was the chief problem. The difficulty was surmounted by con- structing auxiliary bunkers for the high-grade southern Illinois coal. They were constructed of wood and were set almost against the fronts of the 500-hp. boilers in an elevated position so that they could be emptied into the stoker hoppers during peak loads by operating a metal-bound wooden gate. The clear- ance between these bunkers and the boiler fronts was just suffi- cient to afford ventilation and to give space for operating levers. The auxiliary bunker in front of each 500-hp. boiler holds 3 tons of coal. Coal was delivered to these auxiliary hoppers by the same machinery that conveyed coal to the overhead bunker that holds the supply of ordinary coal. When the high-grade coal had to be distributed chutes were arranged under the con- veyor so that the coal would be dumped into the auxiliary bunkers instead of the main bunker. With underfeed stokers it was possible to get as much as 300 per cent of rating out of tlie boilers with this arrangement, but with the chain-grate stokers 175 per cent of boiler rating was about the limit that could be obtained. At the Fort Dodge (Iowa) Gas & Electric Company, which is under the same management as the Davenport company, the same idea was utilized in a different way and for a different purpose. In constructing the plant permanent arrangements were made to 16 CUTTING CENTRAL STATION COSTS fire two kinds of coal in order to reduce the investment which would otherwise be necessary for additional steaming equipment. The boiler plant at Fort Dodge consists of 500-hp. boilers with a sectionalized 17-ton bunker divided into two equal parts. One part is for Iowa coal and one is for southern Illinois coal. Dupli- cate spouts are provided to each stoker hopper. During the peak, or at times when transmission line failure places extra load on the plant, it is possible to get at least 20 per cent increase in rating over the best that can be obtained with Iowa coal. It may be possible to get even better performance. The great saving in this instance comes, however, from the saving of investment in one entire boiler equipment, which would amount to around $22,000. UNIFORM FUEL BED ESSENTIAL A fuel bed that is not of uniform thickness, condition and porosity cannot be productive of the highest efficiency. The con- dition of the fuel bed is often made worse by the excessive and unintelligent use of slice bars and pokers for the purpose of keep- ing up steam pressure. This results in several losses: (a) It makes the fuel bed uneven in thickness or distribution, causing holes, with resultant loss due to excessive air; (b) stirring up the fuel bed generally causes much smoke and soot, which lowers the heat-absorbing capacity of the plant by forming a coating on the boiler and economizer heating surfaces and results in a greater heat loss in the flue gases; (c) stirring up the half- consumed coal and coke brings the ash to the top of the fuel bed, where it fuses and runs together, making clinkers. This action renders part of the grate surface ineffective by closing off the passage of air. FUEL ECONOMY WITH BONUS SYSTEM One of the objections commonly raised by engineers who do not wish to establish a bonus system in the boiler room is that it tends to encourage dishonesty by the firemen. They contend that under such a system the men must be trusted to weigh coal and report all readings and that there is a tendency on their part to "juggle" the figures so that the bonus will be secured regard- less of the real economy obtained. THE BOILER AND ENGINE ROOMS 17 However, if the bonus is based on the weight of coal at the mine and on the kilowatt-hours delivered to the switchboard, this objection is obviated, according to a company in the West which operates an 11,700-lip. boiler room. The men in this plant are provided with everything needed to assist in operating it efficiently. A permanent steam leak is a thing unknown. As soon as it appears a man is on the job fixing it, because in every free steam jet he sees his bonus escaping. Although the plant burns lignite, it has been possible since this system was installed to get an average economy of about 2.9 lb. of fuel per kilowatt-hour. It also keeps the men interested in the operation of the plant and creates a better feeling. PREVENTING FURNACE EXPLOSIONS Probably every one who has operated boilers has at some time encountered the furnace explosion that blows fire doors open and singes the fireman's hair with the hot flame or blows coal particles into his face or eyes. The incident is not uncommon and, al- though potentiall}" a dangerous occurrence, fortunately in most cases causes only temporar}' disability. The use of so-called low- grade fuels at this time of coal scarcity and high prices for marketable coal tends to increase the seriousness of furnace explosions. A brief discussion of their cause and prevention, based on the experience of Gilbert Rutherford may therefore be of value. Furnace explosions happen either when the furnace door is opened or when it is closed. The reason for the explosion is the same in both cases, but the manner in which the explosion is brought about is different in the two cases. Consider an instance w^here a furnace is incased in a setting that is new and airtight so that air infiltration is eliminated by plastering up cracks and crevices, etc. No air enters above the fuel bed, and the furnace chamber is filled with combustible gases. The fire doors are closed and the furnace is operating, and at fairly low rate of combustion, which means comparatively high draft for a thick fuel bed. The fireman now opens the fire door to throw on some more coal or to look at the fire or to rake it over. There being a difference of pressure between the inside and the outside of the furnace chamber, such that the air rushes 18 CUTTING CENTRAL STATION COSTS from the outside to the inside, the air from the boiler room is caused to rush in immediately and mix with the combustible gases above the fire. Combustion occurs instantly and with such rapidity that it has an explosive effect, blowing out the gas and coal into the face of the fireman. The simplest remedy is to maintain balanced pressures, or nearly so, between the inside and outside of the furnace chamber. Another common cause of explosion is in cases where the fur- nace doors are closed after being opened. Suppose a fireman throws a shovelful of slack coal — for example, anthracite dust — upon the fire. To prevent cooling the fires he opens the door wide, throws in the coal as quickly as possible and shuts the door again immediately. While the fire door is open the furnace set- tings fill with air, partially at least. The slack coal thrown on the fire spreads over the fuel bed and combustible gases are dis- tilled. The gases rising from the fire may contain as much as 80 per cent of combustible. This mixes with the air entrained in the settling, the mixture becomes ignited, a small explosion occurs, and the firedoor of the furnace is blown open with con- siderable force as a consequence. The banked fire may constitute a danger in several ways, a danger that can be largely removed by remembering that it is possible and taking the simple precautions which follow. The cause is evidently that virtually all air supply to a banked fire is shut off so that the distilled gases do not have an opportunity to burn. As a result, if the proper quantity of air is acciden- tally admitted a violent explosion is liable to occur. To prevent the dangers of an explosion from this cause it is important to shut the furnace and ash-pit dampers sufficiently to prevent air passing through the fuel bed any faster than is required to keep the fire alive; close the flue damper as much as possible without impeding the escape of the gases distilled by the banked fire and allow air to enter the furnace above the fuel bed. By maintain- ing air circulation above the fuel bed and through the flue damper stagnant explosive mixtures if formed are able to escape. To prevent explosions occurring when opening the bank prepara- tory to bringing the fire back to active operation the flue damper should be opened some time before closing the air inlet over the fire. Then, after the combustible gases have had accelerated cir- THE BOILER AND ENGINE ROOMS 19 culatioD, it is safe to open the fire dampers, and later the firedoor, to start up the fire again. The crux of the matter of furnace explosions is the control of the air. The air required for complete combustion, which means highest combustion efficiencies, is different from that required for explosion. ^Maintenance of approximately equal pressures out- side and inside of the furnace, which is accomplished easily wliere the balanced-draft system of automatic control is employed, tends to accomplish this automatically. However, care should always be exercised to safeguard the furnace and the firemen, and the need for this is greater where coal dust and coals of small i)ai'- ticles are used. BOILER-ROOM MANAGEMENT PLAN The best practice for making a fireman is to select a youn^? man and teach him the job, it was pointed out by T. N. AVynne, Vice-President and Chief Engineer of the Indianapolis Liuht & Heat Company, before the Indiana Electric Light Association. This course of instruction should last at least two years, and his time should be divided between operating and repairing. By repairing grates and stokers and cleaning and repairing boilers the student fireman familiarizes himself with the apparatus he is to operate and hence can fire with much greater intelligence. Too much time or pains cannot be taken with a man who is to handle the company's coal. The fireman must be intelligent and honest — intelligent so that he can understand his instruments, and honest so that he will not make these instruments lie. In the average plant the fireman is turned loose on the coal pile and his job is to keep up steam. Usually there is no reference made as to how he is to do this, since he is supposed to have completed his education in the dim past and to require no further instruction. Experience has shown that the average fireman must be watched very closely or he will do extremely wasteful things. As a general rule, espe- cially in inclined-stoker or hand-fired plants, the fireman will fire and sit down, fire and sit down, and follow this plan throughout the watch. He will try to make his periods of sitting down last as long as possible by firing heavy and then letting the steam drop as far as he dares. He then starts a new cycle. The 20 CUTTING CENTRAL STATION COSTS remedy for this is not to allow the fireman to sit down at all. This is made possible by having the fireman stand eight-hour watches and allowing no chairs or benches in the boiler room. This is not a hardship to the fireman. When he knows he is not supposed to sit down, he interests himself in his work and forgets about quitting time. This results in better and steadier fires and higher economy. A fireman should not be allowed or required to do any other work than attend to his fires. It is the practice in some plants to require the fireman to look after pumps, heaters, etc. This of course is practical in a very small plant, but in larger plants it is decidedly not so. It gives the fireman an excuse for poor fire regulation. He cannot be blamed for having a wasteful fire if he is at that moment packing a pump. A certain number of instruments are absolutely necessary in order to determine the degree of economy being obtained by the "".' 1 ] 3 1 4 1 5 1 V 4 J 1 . 1 ' 1 • 11 • 1 ' .1 1 ?llly d u,l IH ii i ih iil lU ill iil. iill nu .1 ii i M 111 !'L|. LJ ]S ij 'f^ .1 T i^ 1 ': 1 ' 1 i 1 : I 1 1 J 1 ^ 1 . . 1 : ' > 11 t 1 i ' . 1 ■ it It 1 1 • „ ' 1 ' i« , II ^ 1 t N 1 _' J , 1 1 1 1 • 1 , 1 1 [ J . 1 1 i . . 1 ' It "-X 1 : 1 1 1 1 ' ! M M RtPAlt PAR-ni ii«n Fig. 4a — Complete Boiler-Plaxt Record boiler and grate. A boiler and grate has a maximum efficiency at a certain rating. This rating should be found by an actual boiler test. This point of greatest economy is usually around 160 per cent of boiler rating. This rating should be maintained continuously, except of course in cases where it is necessary to THE BOILER AND ENGINE ROOMS 21 crowd the boiler, as at peak load. This is where the underfeed stoker has the advaiitag'e over the other types. It can ])e oper- ated during off-peak hours at the point of highest efficiency and crowded, as has been demonstrated, to 400 per cent of rating during peak hours. Operating at 400 per cent is decidedly un- economical, but it is no more so than carrying banked boilers. The instrument to give this information regarding rating is the steam-flow meter. This instrument is the most essential of all the appliances of the boiler room. The B.t.u., ash, sulphur and moisture must be determined for the coal being burned. Increase in ash and moisture decreases the B.t.u. and consequently increases the freight bill and main- tenance cost per thousand B.t.u. Whenever there is a coal short- age it is next to impossible to get the desired quality of coal, but no let-up should be made in the demand for the best coal avail- able. Sulphur affects the rating which can be obtained from grates, especially of the inclined type, but it is not an appre- ciable factor on chain grates or certain kinds of underfeed equip- ment. Necessarily a calorimeter and some sort of coal-weighing apparatus should be used. A sample of coal should be taken from each car so that the entire car will be represented in the sample. A car sample should weigh about 1000 lb. (453 kg.). This sample should be handled in the manner laid out by the American Society of IMechanical Engineers. The weighing of the coal and ash can be done on scales suited to the purpose of the particular plant. Special pains must be taken at all times with the fire. At normal loads a thin, fast fire is probably the best. With a thin fire holes are more apt to occur than in a thicker one. Hence the thin fire needs more attention, and this may account for the fact that the thicker fire predominates. A draft gage will tell the condition of the fire better than anything else and eliminates opening the inspection door so often to look at the fire. Opening the inspection door means a momentary cooling of the gases. When the first boiler test is made the draft over the fire neces- sarv^ for different thicknesses of fire and boiler ratings can be determined. These values can be plotted so that for any rating the thickness of fire is known, as well as the draft necessary and, in the case of stokers, the stoker speed. 22 CUTTING CENTRAL STATION COSTS ttt**t»»*i*tt»i» g:|jliitcii>'i«i>i«B ii Mil mil iiiinl ^ 9. THE BOILER AND ENGINE ROOMS 23 Two (lraft- — H Temp Loss [^Condensation _oss-- -->■ 1 1 1 1 1 . 200 400 600 800 1000 B. t. u. leoo 1400 leoo isoo Fig. — Components of Total Loss Resulting from Uncovered Pipes Through Condensation of 1 lb. of Steam at 150 lb. Presslt^e Many steam plants have their main steam lines covered with in- sulation of some kind, but it is a very common practice to omit the coverings on valves, flanges, drips, feed pipes and other minor fittings, often because of a fancied difficulty in providing easily removable coverings. They are also great heat wasters, however. The amount of heat, for instance, wasted by one pair of uncov- ered 10-in. (25.4-cm.) flanges will probably amount to a ton of coal a year. Removable covers are easily made with a little fine chickenwire and some canvas, burlap or muslin, covered with plastic insulating material. They can be made in halves or sec- tions and held in place by wire wrapping. Boiler tops, ends, drums, breechings and walls all need proper insulation. In the latter instance it will protect against air infiltration as well as from heat loss. A thickness of from 2 in. to 3 in. (5.1 cm. to 7.6 cm.) of covering is the least that should be used. Writing ^ several years ago. Professor Mac^NIillan said : ' ' The saving due to the use of proper covering is so great that . . . the cost per year rather than the first cost should be the only consid- A ■Or O D 2000 E?00 2400 Z^ ^ §400 a. _rf^ y y ^ 300 ^ y' ^ 13 14 B 6 7 d 9 10 II 12 Time in Minutes x>Qr Blow FlG. 18 — Total Steam Required for Period Blower is in Operation the furnace, and warping. The objection last named, warping, has always been a serious problem. It is a well-known fact that metal begins to warp long before it reaches a temperature that will cause corrosion or burning of the metal. For that reason it is necessary to construct the element so that it will have strength to resist the warping ; for as soon as this action begins the element will be thrown out of line, it will bind in the bearings and the operator will be unable to turn it. The initial cost is comparatively small when compared to a 5 per cent saving in the fuel bill, the reduction in labor and the convenience of operation. Destruction of the elements near the fire has been obviated to some extent by the use of special metal THE BOILER AND ENGINE ROOMS 63 having- high heat-resisting qualities and by so placing the ele- ments that they are protected from the direct heat of the furnace when in the non-operating position. Corrosion, due to back suc- tion of the boiler gases into the blowing elements, has been re- duced by the use of special air valves, and special precautions have been taken to drain the piping system of the blower to pre- vent condensation being forced out onto the heating surface to interfere with soot removal and to corrode the metal. These various improvements, better placing of the elements and nozzles of improved design have so perfected the mechanical blower that, according to reports from numerous users, the services rendered are excellent and the maintenance charges are comparatively small. While users of the mechanical soot blowers realize that they are getting better heat transfer, that the flue gases are lower in temperature and that the boiler efficiency has been improved, there is a lamentable lack of specific data showing the saving actually effected and the average cost of maintenance. The blowers have been installed. They are giving satisfaction. The boilers will carry more load, and it is known that the flue tem- peratures are considerably lower than previous to the installation. During the first two or three years of use repair parts are re- quired occasionally. Depending upon the service, the average life of the blower is at least five or six years. The labor of blowing has been reduced, and as the work is less arduous, it is performed more frequently and with better results. Such was the gist of replies from a large number of power- plant owners and engineers to whom inquiries had been sent by the Electrical World concerning the saving in fuel and labor effected by the installation of mechanical blowers, the cost of maintenance and the degree of satisfaction the blowers gave in service. The substance of some of the replies, more specific than others, is presented in the following: The Iowa Falls Electric Company has equipped three Edge Moor water-tube boilers of the four-pass type with soot blowers. Two of the boilers were rated at 410 hp. and the other at 550 hp. The boilers had previously been blown by hand, and the work required the full time of one man at a cost of $850 per year. In the company's opinion it took a remarkably good man to stand up beside a hot boiler and blow every tube. Frequently some of 64 CUTTING CENTRAL STATION COSTS the tubes were missed, and the result was a reduction in efficiency. Besides, a man could not hold a hose carrying 175-lb. (12.3 kg. per sq. cm.) steam pressure. It had taken the company two months to get all of the old scale off the tubes caused by blowing them with wet, low-pressure steam. The principal advantage of the mechanical blower in its estimation was the fact that full boiler pressure could be used and that better results were ob- tained. Since the installation of the blowers the services of the man previously mentioned had been dispensed with, and the fire- men were blowing the tubes twice on every shift. The saving in coal was placed at 15 per cent. The blowers had been in service one year, and the maintenance expense had been the cost of 1 pint (0.47 1.) of oil to lubricate the swing joints. The Iowa Railway & Light Company of Cedar Rapids had in- stalled mechanical soot blowers on twenty-nine Edge Moor water- tube boilers during a period extended from 1909 to 1918. The company knew that the blowers were a great help both in labor and economy, but could give no definite figures. It had been found that the blowers would not keep clinkers off the first row of tubes. Here was a chance for improvement. In the plant of the Indianapolis Light & Heat Company four- teen boilers, ranging in size from 500 hp. to 800 hp., were equipped with mechanical blowers. If properly operated, the blowers saved approximately 15 per cent in fuel and labor. About 121^^ per cent of this saving was attributed to higher boiler efficiency and 2^/^ per cent to a reduction in labor cost. The maintenance had been approximately $5 per installation per month. The Richmond Light & Railroad Company had blowers on ten 606-hp. B. & W. boilers, equipped with Tajdor stokers. The maintenance on the blowers, which had been installed from one to two years, had been practically nothing. The company had no accurate data to show the saving in coal and labor, but was satisfied that the blowers were a good investment. The Edison Electric Illuminating Company of Brooklyn had in use blowers on seventeen B. & W. boilers averaging 650 hp., and forty-five additional units were being installed. Installation work had begun in November, 1916, and no definite figures as to fuel saving are available, as the majority of the boilers were THE BOILER AND ENGINE ROOMS 65 still blown by hand. In the opinion of the operating eng-ineer there was no (luestion that the boilers were much cleaner by the use of the mechanical soot blower, and as a result a saving in fuel must result. When all of the soot blowers were installed, the labor saving would eliminate the services of five men and would amount to about $13 per day. Soot blowers on 4900 hp. of Stirling boilers are in use at the plant of the Indiana Railways & Light Company of Kokomo, Ind. 1500 14 00 "21300 V) ^1200 gllOO 1 1 000 ^ 900 *S«oo w 700 E 600 I 600 400 JOO r< * ^ ^ ^ ^ ^ ^ ^^^ ^ ^ ^ ^ "^ ?^ 1^^^ r^ P^ .y ^ y^ X^ r#' ^ >5 ^ -^ <^ ^ ^^ <^ e4\ i 'j^ V> ^ ^ ^ ^ \y ^ w ^ r-^ ^ -11^ y J^ ^ w ^ 6 . 7 Ti m e in 8 9 Minutes 10 per II Blow 14 P^G. 10 — Steam Consumption of 2-in. Blower for Various I'hessures No tests have been made to determine the percentage of saving. Cleaner tubes so clearly indicated a saving that the question had not been analyzed. It had been their experience that the soot blower complete had to be removed in from five to six j^ears. Four 750-hp. Bigelow-IIornsby boilers in the plant of the Salem Electric Lighting Company of Salem, Mass., had been equipped with soot blowers in 1915 ; five blowers were installed on 280-hp. Heine boilers in the plant of the Rockland Light & Power Company of Nyack, N. Y., in 1914, and in the same year a 600-hp. B. & W. boiler of the Maiden Electric Company of ^lalden, Mass., was equipped with a blow^er. In the plant first mentioned the saving in labor was $675 per year, in the second plant $411 per year, and in the Maiden plant the labor saving was undetermined. Blower repairs in the three plants had been negligible. In the opinion of the engineering manager controll- ing the three properties there was no question that there had been a saving in fuel on all the boilers equipped with mechanical soot blowers, as it was possible to clean the tubes twice in twent.y-four 66 CUTTING CENTRAL STATION COSTS hours so that the heating surface was maintained in much better condition. No exact data were available. The Central Hudson Gas & Electric Company of Poughkeepsie, N. Y., had equipped six of eight Stirling boilers with mechan- ical blowers. These blowers were much more effective than the compressed air they had previously used, and there was a con- siderable reduction in labor. Installation of soot blowers on two 400-hp. Heine water-tube boilers in the plant of the Chester Valley Electric Company of Coatesville, Pa., in the year 1911 had resulted in a saving in the operation of the plant roughly estimated at 5 per cent. The above figure was considered conservative and was divided into 1 per cent in labor and 4 per cent in fuel. The maintenance charges, which had been small, were placed at $100 in seven years. With blower installations on two 350-hp. Heine boilers and two Stirling boilers for several years, the Texas Power & Light Company placed the cost of upkeep at $5 per blower per year. A saving in fuel of approximately 10 per cent was estimated over hand blowing. The public lighting plant of the city of Detroit had installed soot blowers on two 685-hp. Stirling boilers on April 21, 1916. To clean the soot from two 400-hp. Stirling boilers by means of a steam hose from ladders required the labor of two men for about three hours. With the mechanical blowers the battery of two 685-hp. boilers was cleaned by one man in one-half hour, the ratio being twelve to one in favor of the mechanical blower. So far there has been no maintenance expense. One of the large central-station companies of the country has equipped fifty-five boilers with mechanical soot blowers. These blowers are of competitive types, and a few of home manufacture. Fifteen of the installations have been made on Stirling boilers rated at 2365 hp. that operate all the way up to about 200 per cent of rating. On overload the temperatures are high and the conditions severe, so that it has been found necessary to assist in the further development of the blowers. To clean one of the large boilers by hand requires twelve to fourteen hours ' time with two men operating. These men receive 38 cents per hour, so that the labor cost for hand blowing averages about twenty-six hours THE BOILER AND ENGINE ROOMS 67 of 38-cent time, or just under $10 per 2500 boiler-hp. per twenty- four hours. With soot blowers installed two men blow a boiler in about one hour. They blow each boiler three times per day, so that the total labor cost approximates $2.30 per 2500 boiler-hp. per twen- ty-four hours. Thus the labor item is reduced to less than one- fourth, and the boiler has the advantage of three cleanings per day. The job is much better done, and no useless air is admitted through open doors. The effect of this factor wdll be appreciated when it is noticed that it takes from twelve to fourteen hours to blow one of the boilers by hand. To clean one of the big boilers with a mechanical blower re- quires about 3500 lb. of steam per blow. Three operations per day w^ould require about 10,500 lb. (4762.7 kg.) of steam per 2500 boiler-hp. every twenty-four hours. The maintenance charges on soot blowers had not been sep- arated from certain other somewhat similar costs, but it was estimated that soot blowers properly installed could be kept in good operating condition with a maintenance expenditure of not over $200 per 2500 boiler-hp. per year. The average charge had been higher than this, but it was due to the fact that certain parts as originally designed and installed had given out fre- quently and had to be replaced. Owing to imperfect methods used for measuring flue-gas temperatures accurate data wert not available to indicate the thermal advantage obtained from the use of soot blowers. It was believed safe to assume, how- ever, that mechanical soot blowing maintained a flue-gas tem- perature about 30 deg. to 40 deg. lower than could be main- tained with hand blowing, and unless the latter operation was completely and conscientiously done, the difference would be more nearly 80 deg. to 100 deg. less. SAVING EFFECTED BY USE OF SOOT CLEANER According to a soot-cleaner manufacturer, approximately 18.3 tons of coal is saved by each foot of pipe during the lifetime of the cleaner. In addition, it is said that each foot of pipe elim- inates one man's labor each da}^ which is usually required to blow the pipes with steam. Since the average water-tube boiler requires about 200 ft. (61 m.) of pipe, it is not di^cult to com- 68 CUTTING CENTRAL STATION COSTS pute the total money saved or the money saved by the reduction of labor cost alone on the above basis. If it is assumed that boiler-room labor can be had as low as $2 per day, the labor saving with the average cleaner is $400 for the lifetime of the cleaner. As for coal saving, if it is assumed the price of coal is $4 per ton and 200 ft. of pipe cleaner, the money saving for the lifetime of the cleaner will be about $14,600. This amount added to the labor saving makes the total $15,000. Although these figures vary with labor and coal cost, they can easily be adjusted to suit any conditions. The estimates are made for boilers operated at 140 per cent rating with an average coal consumption of 4 lb. (1.8 kg.) per boiler-horsepower per hour, boilers operating twenty-four hours per day and 325 days per year. The further assumption that the life of a cleaner is seven years is verified by the experience of the United Electric Light & Power Company, New York City, which installed soot cleaners on thirty-two boilers five years ago, the cleaners having shown only slight signs of wear. Moreover, cleaners now made have a much higher safety factor than those installed five years ago because of the cast-iron-sheathed elements with which they are now equipped. MECHANICAL INSTRUMENTS NEEDED IN A POWER HOUSE Following is a list of instruments and measuring equipment considered essential to the most economical operation of the steam end of a modern power station, as outlined recently before Ohio station operating men by C. E. Lewis of Toledo : For Coal. — Track scales; choice of spiral spout meter, auto- matic scales at each point, weighing larry, weightometer. Coal calorimeter. For Furnaces. — Draft gages at chimnej^, at outlet of econo- mizers, at uptakes of boiler and over fire ; choice of U-tube type, oil-filled differential type, indicating bellows type, recording types. Pressure gages on wind box (if forced draft), U-tube type, recording type. Recording flue-gas thermometer. Record- ing stoker speed meter. For Boilers. — Steam-flow meter on each boiler ; choice of Pitot- tube type, Venturi type, orifice type, combination recording THE BOILER AND ENGINE ROOMS 69 steam flow, air flow, flue-gas temperature and indicating draft meter. Recording superheat thermometer. Recording blow- down meters. For Economizers. — Four recording thermometers for gas en- tering, gas leaving, w^ater entering and water leaving. For Feed-Water Heaters. — Water meter on make-up line, on condensate line and on line leaving heater. Two recording ther- mometers for water entering heater. One recording thermometer for water leaving heater. Level recorder. For Feed Pumps. — Indicating gage on suction and on dis- charge. Bi-record pressure gage. For Turhines. — Indicating gages at throttle, at different stages, on bearing oil. Recording pressure gage. Superheat thermom- eter. Mercury vacuum gage. Barometer. Indicating thermom- eters. Hydrometer for air washer. For Condensers. — Indicating or recording thermometers, or both, at exhaust steam from turbines, discharge water, injection water, air suction, condensate, condensate leaving reheater. MEASURING DEVICES HELP PLANT ECONOMY The one 550-hp. and two 410-hp. Edge Moor hand-fired four- pass boilers at the plant of the Iowa Falls (Iowa) Electric Com- pany were being stoked in a more or less haphazard fashion when a new chief engineer was hired. The first thing he did was, in his own language, "to let things go blindly, as they had been going, to get a line on the firemen." This resulted in the dis- covery that firemen were piling a lot of coal into the furnaces, then sitting down leisurely while the steam ran up to the pop- ping-ofl^ point and then dropped back 25 lb. or 30 lb. per square inch (1.75 kg. or 2.1 kg. per sq. cm.). At this stage they would ''slug" the fire again. This was the cycle of operations day after day. This resulted in the installation of a recording steam pressure gage. It required very little encouragement to create a friendly rivalry between shifts to see which could make the best charts. Now these same firemen have become so proficient that, with only an occasional glance at the chart, they keep the pressure range within 5 lb. per square inch (0.35 kg. per sq. cm.), which is very good for hand firing. 70 CUTTING CENTRAL STATION COSTS When this stage was reached the chief engineer, using a single Orsat machine, decided to look into the condition of the COg. The first samples taken from the first pass showed from 5 per cent to 6 per cent, indicating about a 35 per cent loss of fuel. The draft was then cut down over the fires and increased under the fires, and this showed a gain of 2 per cent in the COg. While accurate draft-measuring instruments were not available, this procedure as a cut-and-try process was continued until the sam- ples of COg show 13 per cent to 14 per cent and it was possible to carry the peak load without changing the draft. The draft is now about 0.3 in. (0.7 cm.) over the fires. When the first pass showed this much improvement, samples were taken in the last pass. These showed 8 per cent CO^. Ex- periments with the third pass gave the same results, showing that the baffling was all right. A search for air leaks was then started, which revealed a bad leak in the header. After this was stopped it was possible to get as high as 15 per cent CO^. The boilers are now covered with a plastic cement which is very effec- tive in keeping out air. On the whole, the plant is operating much more efficiently, owing to the installation and use of proper measuring instruments. CHEAP SOLUTION FOR ORSAT APPARATUS By using the waste solution from Edison batteries for the liquid potassium hydroxide usually required for a COg device, the Cit- izens' Light & Power Company of Adrian, Mich., has found that great economy can be effected. One filling of this solution will last for a month of testing and represents an amount of potas- sium hydroxide that costs about $2.75, whereas the return value of the battery solution is only about 10 cents. Furthermore, the time and trouble required for making up the solution are elim- inated. NOZZLE FOR CLEANING SURFACE CONDENSER TUBES A simple and efficient nozzle for cleaning surface condenser tubes, which is far more rapid, yet more thorough, than the usual form of rod and brush, may be utilized where air under pressure is available. The cleaning outfit consists essentially of a piece of ^/4-in. (0.6-cm.) pipe bent to shape, a reducer, a %-in. THE BOILER AND ENGINE ROOMS 71 (1.3-cni.) T, a pair of regulating valves and suitable lengths of air and water hose. Air is required under 60 lb. per sq. in. (4.2 kg. per sq. cm.) pressure or more. A cheek valve should be placed in the air line to obviate any chance of water getting back into the line. The head is taken off at one end of the condenser; at the other end only the hand-hole plates are re- moved. The nozzle is rapidly moved from tube to tube at the open end, and the dirt, consisting mostly of mud and seaweed, is expelled from the tube by the scouring action of the air and water. After the washing is complete, the ejected mud is scooped out through the hand-holes at the other end of the condenser. By this means one man can clean a 4000-kw., 10,000-sq. ft. (900- sq. m.) surface condenser, containing approximately 3400 15-ft. (4.6 m.) 2%-in. by %-in. (7.3-cm. by 1.9-cm.) tubes, in six hours, not including the time required for removing and replacing the condenser head and plates. The operator must wear a rubber coat and a helmet. It is stated by the station operators of the San Diego Consoli- dated Gas & Electric Company, who utilize this form of nozzle, that this method of cleaning is a great labor saver. When the air and water nozzle was first used hollow cylinders of mud and sewage were ejected from many of the tubes, showing the new method to be a decidedly thorough cleanser. It is understood that some central stations use sand blasts for cleaning tubes. With the particular forms of sediment encountered in San Diego, no scale being present, sand appears to be unnecessary, and the wearing action which may result from the use of sand is not ex- perienced. COAL PILE SPONTANEOUS COMBUSTION Heat due to oxidation rather than pressure was given as the main cause of spontaneous combustion of bituminous coal by Prof. H. H. Stock of the University of Illinois before a meeting of the Western Society of Engineers. He said that coal should be stored so as entirely to exclude any air, or else adequate ven- tilation should be provided to keep the coal at a low tempera- ture. Any intermediate conditions are dangerous and should be avoided. Among precautions which were suggested for preventing spon- 72 CUTTING CENTRAL STATION COSTS taneous combustion were: Coals of different varieties should not be mixed while in storage, and the coal should not be piled high on account of the difficulty of moving it in case of fire. If sufficient heating occurs to raise the temperature to 150 deg. Fahr., close watch should be kept on the pile ; if the temperature increases to 175 deg. Fahr., it should be moved and cooled before more coal is added. Equipment for storing coal should be arranged to make it possible to move the coal quickly in case of an emergency. To avoid the starting of fires pieces of wood and greasy waste should be carefully removed from storage piles and the coal in storage should be kept away from external sources of heat, such as steam pipes. Common methods for testing coal piles for heat are as follows : Watching when the pile begins to steam; observing the odor, which is that of either burning bituminous matter or burning sul- phur; inserting an iron rod into the pile and when drawn out testing it with the hand; inserting a thermometer into a pipe driven into the pile ; observing spots of melted snow on the pile. He said further that opinions differ in regard to the critical temperature in piles of coal. Professor Parr of the University of Illinois is of the opinion that bituminous coal can be stored without appreciable loss of heat value, provided that the tem- perature is not allowed to rise above 180 deg. Fahr. How close to this temperature a pile should be allowed to heat is largely a matter of judgment, for if the rise in temperature appears to be decreasing rather rapidly it may be safe to allow it to approach 180 deg. Fahr., whereas if the rise is steady and regular it is wise to load out the pile before the danger point is reached. The time also depends upon the means available for loading out the coal, for at a plant equipped with large grab buckets and means for rapidly handling the coal a higher temperature can be per- mitted than where a considerable time may be required to load out the coal. A person in charge of a certain kind of coal under certain climatic conditions will soon learn what the danger point is, and it is impossible to set any critical temperature that will apply to all coals under varying storage conditions. The only safe rule is to watch the pile closely and get ready to load out the coal when the temperature reaches 150 deg. Fahr. and to move the coal if the temperature reaches 175 deg. Fahr. An interesting experiment has been carried out at the Uni- THE BOILER AND ENGINE ROOMS 73 versity of Illinois in stocking No. 6 Illinois coal mined near Georgetown, 111. For several years it has been customary for the university to stock 4000 tons to 5000 tons of coal on the ground in piles about 12 ft. (3.7 m.) high, the coal being thrown from railroad cars onto the piles and distributed by scrapers. At times fires occurred in these piles. During the summer and fall of 1917 a pile of about 10,000 tons of coal was placed on an old tennis court which furnished a hard foundation. This coal was piled to a depth of 10 ft. (3 m.) or 12 ft. (3.7 m.) and surrounded on three sides by a light fence 7 ft. (2.1 m.) high. The coal was transported to the tennis court by means of a motor truck, and the entire surface of the ground was covered to a depth of from 2 ft. to 5 ft. (0.6 m. to 1.5 m.) . This layer of coal was then rolled with a heavy roller to pack it down tightly and exclude the air as much as possible. The fence, of course, assisted in excluding the air around the edges of the pile. Plank roads were then laid over the top of the pile so that the motor truck could dump more coal on top of the layer which had been rolled. This process was repeated contin- uously until the pile was completed. This method of storing coal proved rather successful. While heating developed in a couple of places where other coal had been mixed with the screenings, the method otherwise proved entirely satisfactory. The cost of storing and reclaiming coal handled in this way averaged about 40 cents per ton. DETERMINATION OF INSULATION ECONOMY By calculating the volume of heat loss from insulated pipes and adding the fixed expense and cost of maintaining the insulating material a decision can be reached as to the expenditure which can be economically made to insulate pipes. Curves which take these considerations into account are given in Fig. 20, the actual cost per year per square foot of surface covered being shown direct. The horizontal lines represent the cost of upkeep, and the curves radiating from zero give the value of the heat losses at various temperature differences. The temperature difference to be used is found by subtracting the temperature of the surround- ing air from the temperature of the steam in the pipes. By 74 CUTTING CENTRAL STATION COSTS adding the constant and variable costs the total expense charge- able to insulated pipes is obtained. This is shown by the remain- ing curves. Referring to a handbook or similar source of information, the loss from bare pipes can be obtained and a comparison made. 1.00 zoo 500 400 500 Temperature Difference, Deg. Fahrenheit Fig. 20 — Total Expenses Chargeable to Pipe Insulated with 85 per CENT Magnesia The experiments on which this chart was based were made at the Mellon Institute of Industrial Research at Pittsburg, Pa. In- sulating material known as 85 per cent magnesia was vised in the tests, which covered a year's time. SPONGE-FELT INSULATION PROVES VALUE A 2200-ft. (670-m.) length of outdoor pipe line 6 in. (15 cm.) in diameter transmitting steam having a temperature of 466 deg. Fahr. has been successfully insulated from a low tempera- ture during the winter months by a combination of sponge and hair felt. The sponge is placed next to the pipe and covered with the hair felt. The hair felt will not withstand high temperature but makes an excellent intermediate or superficial covering. The total thickness of the heat insulation on this line is 3 in. (7.6 em. ) , and tests show that the outside temperature is only slightly THE BOILER AND ENGINE ROOMS 75 above that of the air with the latter at 22 deg. Fahr. In the winter icicles formed on the line. ASBESTOS INSULATION CONSERVES HEAT The use of asbestos insulation between the courses of the brick settings of boilers reduces air leakage and conserves heat that is usually wasted with the ordinary air space, according to recent investigations of the United States Bureau of Mines. Firebrick should withstand temperatures up to 3000 deg. Fahr., but it is a good conductor of heat and conducts it six to ten times as fast as the asbestos felt. Red brick conducts heat about five times as fast as the felt. Insulating material with smaller air spaces re- duces convection losses far better than material with the larger air spaces. This practice is especially timely with the present fuel prices, and the result shows that it is not economical to use cheaper insulations for high steam pressures. When subjected to temperatures of 1200 deg. to 1500 deg. Fahr., the disintegra- tion of the better grade of asbestos fibers starts and the material gradually becomes more brittle, not going to pieces, however, much below 1800 deg. Fahr. PROTECTING LAGGING ON SOOT-BLOWER PIPING Sometimes when the side doors in a boiler setting are opened the flash of flame which comes forth is sufiicient to burn the cloth covering from the magnesia which surrounds the adjacent soot- blower steam piping. The result is that the covering becomes very unsightly and the magnesia soon begins to drop from the pipes, leaving them uninsulated. Without a covering on the pipes condensation of the steam will occur, and this is undesirable in blowing soot. To eliminate this trouble the Dayton (Ohio) Power & Light Company in its new power house at Miller 's Ford lias covered all pipes adjacent to the doors with galvanized iron. The sheet metal is applied after the magnesia and duck are in place. INCREASING STATION ECONOMY Southern California being a large fuel-oil producing section, there has as yet been no real shortage of fuel there. However, oil consumption is rapidly increasing, and there are grave possi- 76 CUTTING CENTRAL STATION COSTS bilities of a real fuel-oil shortage in the near future. All pos- sible means are therefore being devised writes J. W. Andree, Assistant Superintendent Department of Generation, Southern California Edison Company, to decrease the consumption of fuel oil. All the water powers of southern California are being util- ized to their utmost, hardly a drop of water going to waste in this section which can be put into use at a reasonable cost. At the Lytic Creek plant of the Southern California Edison Com- pany wells have been sunk in the river bed below the diversion dam, and the underflow of the river is pumped from these wells into the conduit leading to the power plant by motor-driven pumps. On the Santa Ana River water rising below the diversion dams of the upper plants is diverted into the intake of the lower plants. The pipe lines of the Mill Creek No. 3 plant have been cleaned of all vegetable and animal growth to decrease resistance to the flow of water. Nature has lent a helping hand at this plant to increase its output. The winter rains always leave the river bed very rough and full of porous gravel, which encourages a large underflow of water. Early summer rains this year have brought down an abundance of silt and cement-like deposit, which has effectively filled many of the voids in the river bed and thus decreased the underflow, and as a result the flow of this river has been much larger than in other years of equal rainfall. At the Mill Creek No. 2 plant water which flows under the diversion dams is diverted into the canal at a lower point. New buckets are being designed for this plant which should increase its efficiency from 10 to 15 per cent. The waterwheels in the Mill Creek No. 1 plant have been recently overhauled, and the design of the needle valve and tips has been changed to give the highest possible efficiency on the old-type equipment of this plant. Increasing Waterwheel Efficiency. The design of the needle valves and tips of the Azusa plant is being changed to increase the efficiency of the waterwheels. The nozzle tip on one of the waterwheels at the Sierra plant has been made larger to increase the output of the plant during periods of high water. At this plant it is also contemplated to replace the old two-phase, 500- volt generators with 11,000-volt generators of modern design from the Pedley plant, operation of which has been discontinued. By doing this the electrical efficiency of the plant will be in- THE BOILER AND ENGINE ROOMS 77 creased and transformer losses will be eliminated because the generators will feed directly into the 11,000-volt distribution system. All important transmission systems of southern California are interconnected, the larger and more efficient plants being op- erated at full load and the smaller and less efficient plants used only to carry peak loads. Frequency-changer sets have been placed in operation between the systems operating at different frequencies. A 5000-kw. frequency-changer set is in operation at Colton, connecting with the Southern Sierras Power Company, and similar units are in operation at San Juan Capistrano and Magunden, connecting with the San Diego Gas & Electric Com- pany and the San Joaquin Light & Power Company respectively. The Kern River No. 1 plant is being operated at 60 cycles on the San Joaquin Light & Power Company's system, and it in turn is feeding the Mount Whitney Power & Electric Company at the same frequency. At such times as there may be an excess of hydroelectric power on these systems the excess can be diverted to the Southern California Edison Company's system through the frequency changer at ]\Iagunden, or the generators at the Kern River No. 1 plant may be changed to the 50-cycle system. This change can be accomplished with an interruption of only fifteen minutes (on the generator being changed) if all generators are running loaded and with no interruption at all if three or fewer are in operation. To decrease the consumption of fuel oil at the Redondo plant one-third of the total number of boilers have been equipped with furnaces for burning natural gas. Those furnaces are of the multiple-burner type, there being 180 gas jets distributed over the entire floor of the furnace. The gas enters the furnace from the front through five 21'^-in. (63-mm.) extra-heavy pipe laterals extending the full depth of the furnace under the furnace floor. At intervals of about 9 in. (25 mm.) these laterals are tapped on each side for 0.5-in. (13-mm.) pipe nipples, which are capped with standard pipe caps and have a ^i6-in. (5-mm.) hole drilled in the top near the outer end. Over this opening is placed a fire- clay burner tube 15 in. (38 cm.) long and 3 in. (8 cm.) inside diameter. These tubes have a slot cut in one side which straddles the 0.5-in. nipple with the orifice in the center of the tube and 12 in. (30 cm.) from the top. The top of the tube is flush with 78 CUTTING CENTRAL STATION COSTS the floor of the furnace, and baffle bricks are laid over the tube opening to diffuse the gas flame. The furnace floor is supported on 2-in. (5-cm.) standard pipe. This furnace burns the gas very efficiently, and the flame is so evenly distributed that there is practically no danger of burning or blistering of the boiler tubes. To avoid damage to the clay-burner tubes due to expansion of the furnace floor, the floor is loosely laid with mortar containing asbestos. These furnaces are also equipped with front-shot oil burners for use in emergency when there is a failure of the gas supply. While the efficiency of oil burners in these furnaces is not very good, still it is more economical to use them for short periods of gas interruption rather than to warm up cold boilers which are equipped with oil-burning furnaces. The oil burners can be put into operation on instant notice so there is no interruption of the supply of steam. CAUSES OF IMPAIRED TURBINE ECONOMY In addition to its many other advantages the steam turbine has the characteristic of maintaining its original efficiency for a considerable length of time, Josef Y. Dahlstrand, Chief Engi- neer, Kerr Turbine Company, states, if operated intelligently and properly maintained. In the majority of cases it can also be re- stored to its original efficiency with a small expenditure compared to that necessary for the same purpose on an engine. The causes of impaired steam economy with a turbine or turbo- unit in many cases lie entirely outside of the turbine itself. In certain instances, however, the causes are found to develop right in the turbine. When steam economy is impaired it does not necessarily follow that the thermo-dynamic efficiency of the tur- bine affected is decreased. In some cases the thermo-dynamic efficiency might actually be increased. In the following article the steam economy of the turbine only will be considered, rather than the thermo-dynamic efficiency. To Save Coal Operate Turbines at Rated Vacuum. Probably the most common cause of decrease in steam economy, particu- larly with a small turbine, is the falling off of vacuum in the exhaust chamber. Furthermore, it generally results in the most serious loss. THE BOILER AND ENGINE ROOMS 79 The effect of vacuum on the thermo-dynamic performance of the steam turbine is well recognized. Various papers and books have been published with charts giving the percentage of steam saved for each inch of vacuum. As a matter of fact, that per- centage varies greatly with varying steam pressure and varies somewhat with different types of turbines, with capacities, with operating speeds, with quality of steam and, last but not least, with the percentage of the designed load developed. The charts are of two different and distinct types. One shows the difference in steam consumption obtained with turbines de- signed for different vacuums. The other type illustrates the difference in steam performance obtained with a turbine designed for a certain vacuum but operated at a different vacuum, l^oth types are subject to variations, due to all the causes mentioned. Naturally the latter is the one which should be considered in this article. Certain curves are shown in Fig. 21 made by Mr. Dahlstrand from actual test data on a number of 1000-kw. Kerr turbines de- signed for 150-lb. steam pressure (dr,y and saturated steam) and operating at 3600 r.p.m. with varying vacua (27 in. to 29 in., or 68.58 cm. to 73.66 cm.) and loads. These curves may be used with fairh^ good accuracy for turbines rated at 500 kw. to about 3000 kw. Proper correction must of course be made for steam pressure, if this is not 150 lb. These curves are of special interest on account of the fact that they show the effect of vacuum when operating at partial loads. It will be noted that a turbine designed for 28 in. (71.12 cm.) of vacuum, and operating at 27 in. (68.58 cm.), with 25 per cent load, will have a steam rate 12 per cent in excess of that which it would have if operating at 28 in. vacuum and 25 per cent load. If, on the other hand, it was operating at 100 per cent load and 27 in. vacuum, the steam rate will be impaired only 7 per cent compared with what it would have been if operated at the rated vacuum. The explanation of this lies, as will readily be under- stood, in the fact that when a turbine is operated at 25 per cent load the steam is throttled before entering the first stage nozzles to a pressure very much lower than 150 lb., and the number of heat units constituting the difference in available energy be- tween 27 in. and 28 in. vacuum becomes a nnich higher per- centage of the total energy available for use in the turbine. 80 CUTTING CENTRAL STATION COSTS Consulting the entropy heat diagram for a verification of the correction figure, 7 per cent, between 28 in. and 27 in. vacuum, it will be found that from 150 lb. to 28 in. vacuum there is 323 B.t.u. available, excluding the effect of reheating and consider- ing straight adiabatic expansion. From 150 lb. to 27 in. vacuum 30 26 20 ^22K I20 .E 16 S '^ c j; 14 \> S 12 t 10 ^ 8 ■■ 1 ■ 1 Desicjned for I50-It>. \^ K'^ pressure anc^ vacuum from 27' fo 29" ernd- opera-hinc^ at same pressure and varying \ \ V N?" A -N CM -^ Q vacua \ CVi o \ t^; \ \ N V N \ \ ^ N^s \ v1<: \ ^ ^\ \ H^-.K ■* \ > K V, --^ ^ \ ^ \ ^< ^' N, S" "^ & ' -=*^ ^^ 20 40 eO 60 100 20 40 60 60 100 20 40 60 S>0 100 Per Cent. Looted Fig, 21 — Effect of Load and Other than Rated Vacuum on Water Rate there will be found 301 B.t.u. on the same basis. According to this, there is l'V2 per cent more heat available with 28 in. vacuum than with 27 in. vacuum. The correction figure for the latter water rate on this basis should be IV2 per cent. There are certain factors which have a tendency to increase this correction figure. They are : First, the windage losses, which increase with the density of the steam; second, the fact that the nozzle passages in the last stages are too large for the lower vacuum, a circumstance equivalent to operating the last stages at a partial load. These circumstances, however, are generally more than outweighed by another fact. As was mentioned before, an increase in steam consumption does not necessarily mean that the thermo-dynamic efficiency is decreased. On the contrary, it is sometimes actually increased. This happens to be true to some extent with nearly all commercial turbines of small and medium size. The thermo-dynamic effi- ciency^ is largely dependent on the "velocity ratio," or the rela- THE BOILER AND ENGINE ROOMS 81 tion between blade and steam velocities. For commercial rea- sons the turbine frames are actually in many cases somewhat smaller than those which would give the very best efficiency. It might be stated here that future tendencies in steam-tur- bine building will probably follow somewhat different lines from recent practice. Jn.stead of rating a turbine frame at its maxi- mum capacity, without regard for a small loss in efficiency, indi- cations are that the future policy will be to get the maximum efficiency even if at higher cost. As has already been stated, low vacuum is far from uncommon, particularly in small power plants. It is not unusual to find that a turbine designed for 28 in. (71.12 cm.) of vacuum is actually operating at 25 in. (63.5 cm.) vacuum for months, owing to leaks in the exhaust line or some similar cause, with a loss of no less than 16 per cent in steam consumption. The same percentage .Connected to . H. P Steam LJne Fig. 22 — Gland for Condensixg Service loss will be found in coal consumption if the low vacuum is due to air leaks, as this does not lighten the work of tlie auxiliaries but rather increases it. Leaky Glands or Exhaust Pipes Reduce Vacuum. The falling off of vacuum in the exhaust chamber of the steam turbine 82 CUTTING CENTRAL STATION COSTS may be due to a number of different circumstances. The fore- most of these are air leaks. These may develop in the exhaust piping between the turbine and condenser, in the condenser itself or in the turbine glands. Air may also enter through the pis- ton-rod and valve-stem packing on condensate pumps. In addi- tion, air may enter the condenser through the circulating water. The exhaust-end gland of the steam turbine is generally sealed with water or steam, the simplest form of this gland for con- densing service being shown in Fig. 22. This gland is commonly used for impulse turbines. It has three carbon rings with a high-pressure connection. The valve throttling the high-pres- sure steam is opened sufficiently so that the pressure at the right point A is high enough to keep the air from leaking in and at the same time not high enough to cause any excessive leakage along the shaft toward the outside of the turbine. If too great an amount of high-pressure steam is necessary to seal the gland, it is evident that the packing needs to be replaced. Assurance that there is no leakage of air into the gland may be had by ad- justing the seal valve so that a very slight mist of steam escapes along the shaft. In certain cases with low-pressure turbines, where the steam supply comes from the exhaust of a non-condensing engine, steam leaks sometimes develop in the turbine steam line. These are especially common when operating turbines at low loads, in which cases the pressure on the first-stage nozzles is generally below atmosphere. In such cases it is often advisable to install a so-called flow valve in the low-pressure steam line. This valve is so made that it will maintain ahead of itself a constant pres- sure, no matter what the pressure may be on the opposite side of it. It will hence prevent vacuum from entering the engine exhaust pipe, which, as stated above, generally results in infiltra- tion of air through pipe joints or piston-rod and valve-stem packings. The air leaks in piping and condenser are easily detected. The most common method of detecting air leaks at these points is that of bringing the flame of a candle around the joints and noting at what points the flame is drawn toward the point. While air leaks are the most common cause for impairment in vacuum, there are others as well. A condenser which has been in service for a considerable length of time and which has been THE BOILER AND ENGINE ROOMS 83 allowed to accumulate a large amount of dirt on the surfaces will not be able to maintain the vacuum it could give in its original condition. Excessive back pressure is just as detrimental with iion-con- densing machines as impaired vacuum with condensing units. This is not so common as impaired vacuum, but ma}^ be caused through carelessness on the part of operating engineers in leavin«i- exhaust valves partly closed, etc. The effect of increased back ^45 c^ 35 «30 J- 25 I 20 c 15 *> 1 oj 5 o .E ./ WN ■CO/ vz)£y V5/A 16 6 rL.P Over 200 hp. \ V Less than 200 Hp. ^ f^ NDE NS/i NG ^^ ¥ V ^ ^ ^ ^ ^ :>^ :V5 ^ ^ J^ «f**< es^ 5«^ Fig. 23- '/4 '/2 % \h -Effect of Load on Water Rates of Condensing and JS on- Condensing Turbines pressure on the steam economy of non-condensing turbines may be realized from the following table. Increase in Steam Consumption for Eacli Pound of Back Pressure (per cent) 1 iy4 Initial Steam Pressure (lb.) 200 175 150 125 100 75 2 21/. 3 Operation at Partial Loads Is Uneconomical. Next in its effect on the steam economy of a turbine comes the operation of turbines at partial loads. In a great many instances steam tur- bines are ordered for certain loads and designed for these loads. Later on it develops that they are required to operate at points very much below the full load rating of the machine. \\\ sucli cases there generally results a considerable loss in steam econ- omy. The curves shown in Fig. 23 illustrate these losses as found in tests on Kerr steam turbines. 84 CUTTING CENTRAL STATION COSTS The reason for the increased steam consumption at partial loads is obvious. The losses in the turbine do not change in pro- portion to the load but remain nearly constant for any load. Consequently the relation of these losses to the energy available increases for partial loads. The throttling of the steam which is found necessary for partial loads, unless hand valves are used, robs the steam turbine of some of the energy otherwise available. The fact that a turbine is operating at partial load may be seen by observation of a steam gage which is tapped into the ring chamber ahead of the first-stage nozzles. If the pressure under normal operation at this point is considerably below boiler pres- sure, it is an indication that the turbine is operating under a partial load, provided of course that it was designed for only a reasonable pressure drop through the valve. The power de- veloped with any type of turbine is very nearly proportional to the pressure at that point. Turbines should be made to operate normally under the con- ditions for which they are designed. If it is necessary that they should carry overloads, overload valves — either automatic or hand operated — should be used. Internal Leakage Should Be Avoided. Up to this point only those circumstances which arise through steam conditions and from outside sources have been considered. Certain mechanical conditions inside of the turbine may also cause a thermo-dynamic loss in the steam turbine. Foremost among them is internal leakage. This is caused by the wearing out of the packing rings or bushings or the excessive clearance of labyrinth packing be- tween the various stages in the steam turbine. Internal leakage is, of course, most liable to develop where the pressure differences are very great. Therefore, in certain makes of turbines the high pressure steam space is separated from the vacuum chamber with an internal gland. In cases of this kind it is always advisable to watch this gland carefully, as leaks may readily develop through it, causing a considerable loss in steam economy. Internal leakage is particularly detrimental in the high-pressure stages of a machine on account of the low specific volume of the steam in these stages, which results in a large dis- charge of steam through a small opening. Leakage may also take place between the stages along the hor- izontal joints of the diaphragms in a multi-stage turbine. The THE BOILER AND ENGINE ROOMS 85 steam aud moisture may erode the surface of these diaphragms to such an extent that a considerable amount of steam will pass through from stage to stage. Leakage between stages as well as internal leakage may be de- tected by placing a gage in each stage of the turbine to give the pressure in that stage. Comparing these figures with the pres- sures which the turbine had when originally installed will give a good indication as to the condition in which the packings installed in the turbine are. Steam leakage through the high-pressure gland or through the leakage piping on this gland is generally negligible. It is usually sufficiently annoying to the operating engineer, however, to lead him to try to overcome this condition. Generally losses due to this cause are greatly exaggerated by operating engineers. Among the causes for impaired steam economy is excessive clearance between stationary and rotary elements. When this condition exists, Rateau, Curtis and other impulse turbines lose slightly in power. It would be difficult to formulate any definite rule as to the degree in which steam economy is influenced by clearance, as this varies with capacity of machine, nozzle and blade angles, etc. It is advisable, however, to bear it in mind if it becomes necessary to manipulate the thrust bearings. In gen- eral, it may be said that the rotary element should not be farther away from the stationary element than is necessary for the me- chanical safety of the machine. Each case should be considered separately, however, so turbine users should consult with the manufacturers of their machines if information regarding axial clearances is desired. With certain makes of turbines, particularly single-wheel im- pulse turbines, where the total pressure drop is utilized in one single expansion, considerable trouble has been experienced with erosion. This has been the case particularly with turbines in which the relative steam velocity was high — in other words, tur- bines having small wheel diameters or low speeds and operating condensing. Some difficulties have been experienced even with non-condensing turbines as weW, particularly where the steam has been wet. If superheated steam is used, erosion is less common. Blade materials now being used in various types of steam tur- bines utilizing high steam velocities are being improved so as better to resist the erosive action of the steam. Erosion is abso- 86 CUTTING CENTRAL STATION COSTS lutely unknown with other types of turbines on account of the low steam velocities employed. Through erosion of the blade edges the axial clearance between the rotary and stationary elements is increased, which tends to cut down the power developed. Through the fact that these edges are made dull less perfect steam action is attained, which in turn causes a loss in power and efficiency. Deposits on Blades Liable When Forcing Boilers. The de- posits of foreign substances in the turbine blades, blocking or" partly blocking the passages, might be mentioned as another cause of impaired steam economy in turbines. This trouble usually occurs when a turbine is being fed by one or more boilers which are giving about their maximum capacity. It is more serious with some types of boilers than others. In both fire-tube and water-tube boilers there is such active circula- tion of water that the mud and foreign material are prevented from settling in the boiler and are mechanically lifted to the top and carried through the steam lines. In some steel-mill districts the deposit consists principally of a muddy material which is bound together by chemicals existing in the water. At the velocity at which steam enters the blades any slight material carried in the steam will be impelled against the blades with such a velocity that it will form a very compact deposit. In a great many instances the boiler-feed water supply contains large portions of vegetable matter, as well as boiler scale-forming materials. Where this is the case the combination produces a tough, rubber-like deposit which rapidly fills the turbine blades and causes serious trouble. Owing to the immense quantity of steam passing through large turbines a rapid increase of deposits may result even though the amount of material mechanically carried over by the boiler is very small per unit of power. It is, therefore, frequently aston- ishing to note the accumulated deposits when the steam is appar- ently quite pure and clean. Sometimes turbine blades become so clogged that sufficient power cannot be produced and the turbine has to be dismantled and cleaned. Steam that is very wet, when made from water containing scale- forming material, such as magnesia and other salts, will in- variably deposit a scale-like substance over the turbine blades. This is somewhat distinct from the deposits mentioned pre- THE BOILER AND ENGINE ROOMS 87 viously. Tliere are other deposits whieli are more local in character, such as, for instance, deposits which occur in i)ai)cr- mill districts, where a considerable amount of pulp is discharged in a finely divided state into rivers adjacent. The result is that this finds its way into some neighboring power plant where, owing to its fine and light nature, it is carried over by the steam and very rapidly blocks u]) the turbine blades. Several cases have come to the writer's attention where this occurred, the turbine having to be dismantled at regular intervals and the blades cleaned out three or four times a year. There are various means of combating the clogging of blades from the above-mentioned causes which are effective in different degrees. One which is frequently used, particularly for non- condensing turbines, is the placing of a lubricator in the turbine steam line. The oil vapor in the steam lubricates the blade surfaces and prevents the substances from, becoming attached. Even for condensing turbines this method is frequently used, although it would appear not to be entirely advisable in installa- tions where surface condensers are used, on account of oil de- posits which would be found on the tubes. Two instances are known of where this method is used with turbines rated at 10,000 kw. Undoubtedly the most effective means of preventing this trouble is that of installing a large receiver in the steam line. The steam velocity will be decreased greatly while passing through this receiver and the foreign substances will be deposited on the walls. In addition to the receiver there should be in- stalled near the turbine throttle a steam separator which will serve the double purpose of removing from the steam any re- maining foreign substances and extracting a great deal of mois- ture from the steam. It might in some cases be advisable to com- bine these two apparatus and install a so-called receiver-separa- tor, in which case the foreign materials will be deposited on the baffles. GETTING THE MOST OUT OF TURBO-GENERATORS With the advent of the modern horizontal-shaft steam-turbine generator, the ratio of the total kilowatt capacity to the cubical contents of power-plant engine rooms has increased at least two- 88 CUTTING CENTRAL STATION COSTS fold or threefold. The necessity for adequate ventilation must, therefore, be recognized in order that a safe operating tempera- ture for the electrical apparatus may be maintained and extreme engine-room temperatures avoided for the comfort of the attend- ants, according to L. H. Parker and J. J. Preble of the Spray Engineering Company. The enormous quantity of air required for ventilating large generators is perhaps better understood when the actual weights are considered. Assume, for example, a 20,000-kva. machine requiring 65,000 cu. ft. (1840 cu. m.) of air per minute. As this amount of air weighs about 2^/^ tons, the generator will handle an amount of air equal in weight to its own weight in from one-half to three-quarters of an hour. While no one questions the necessity of supplying a generator with a sufficient amount of ventilating air, there are many who do not give the temperature and quality of the air sufficient con- sideration. The turbine manufacturers equip their machines with fans designed for handling the proper volume of air, but upon the consulting engineer, manager or superintendent of the plant falls the duty of seeing that adequate air-conditioning ap- paratus is installed, so that the machines will also receive cool and clean air. One effective device that can be used for this purpose is a properly designed water-spray type of air washer and cooler. Cleanliness and Temperature. Air in almost any locality contains considerable dust and dirt. In the vicinity of power plants it may be assumed that roughly one-hundred millionth of the volume af the air consists of dust, dirt and other foreign particles. This would mean that with a machine handling 65,000 cu. ft. (1840 cu. m.) of air per minute, as mentioned heretofore, a total of 93,600,000 cu. ft. (2,650,000 cu. m.) would be handled in twenty-four hours. On this basis the amount of dirt passing through the machine in this period would be 0.936 cu. ft. (0.026 cu. m.), or 86 cu. ft. (2.4 cu. m.) in three months. A certain proportion of this, because of air swirls and eddies, will necessarily be deposited in the air passages. Such deposits of dirt become a serious handicap to the ventilation. The air passages become partly clogged, causing a decrease in the quan- lity of air handled, and the cooling effect is greatly diminished owing to the fact that air cannot come in direct contact with the heat-radiating surfaces. Air taken from the inside of a power THE BOILER AND ENGINE ROOMS 89 plant usually contains oily vapors, which make accumulations on the air passages rapid. Unwashed air means dirty generators and excessive heating, which not only reduces the electrical efficiency but shortens the life of the insulation. Unless the machines are taken apart and cleaned periodically-, grounds and even burn-outs are liable to occur. The cost of thoroughly cleaning a generator amounts to considerable, and under average conditions this has to be done about twice a year. The expense of dismantling and cleaning a 10,000-kw. unit would be about $500 for each operation, without taking into consideration the revenue lost owing to the machine being out of commission. Since a generator which receives clean air is comparatively free from all such troubles, it is apparent that an air washer will practically eliminate any danger of a serious accident, with a resulting loss that might exceed many times the cost of the in- stallation. As all modern units are designed for a certain allowable maxi- mum temperature in the armature and field windings, the temper- ature of a generator with a given load will be a fixed amount above the temperature of the ingoing ventilating air, which must be well below the critical temperature of the insulation. The cooler the air delivered to a generator, therefore, the greater will be its load-carrying capacity. The permissible load on a turbo-alternator may, therefore, be expressed as a function of the temperature of the ingoing air. This relation ^ is given in Table based on representative 25-cycle and 60-cycle machines. The load is based on a fixed maximum temperature attained by any part of the windings. Since 25 deg. C. (77 deg. Fahr.) is a standard air temperature for elec- trical machinery, the load at this temperature is taken at 100 per cent. The cooling which can be obtained by the use of air washing and cooling equipment varies with the make and type of washer. For use with electrical equipment a washer should be capable of reducing the temperature of the entering air at least 85 per cent, of the initial wet-bulb depression. Table shows the cooling ef- fect with a washer of this class, using some of the higher tem- peratures given above, with different humidities. 1 Curve given in General Electric Review, September, 191:^. 90 CUTTING CENTRAL STATION COSTS It is possible, therefore, with this class of washer to increase the safe load-carrying capacity within the above temperature ranges from a maximum of 22 per cent, to a minimum of 3 per cent. With a washer that will cool to the wet-bulb temperature us. ©€GQ©0O© ©©©©©ooooooooooo OCOOOOOOOOOGOOOGOOOOOOOOOeOOOOO© Fig. 24 — Heat- Absorbing and Cleaning Ability of one Drop More than Trebled by Subdivision there is, of course, a further gain. Consequently, it is fair to assume that under average atmospheric conditions in the United States during the summer months the gain in load-carrying capacity would be at least 5 per cent. When Will it Pay to Install Air Washers? There are various ways of figuring whether an investment in air washers is actually justified. One way is considered in the following: Assume a typical modern steam-turbine power station containing three 10,000-kw. turbo-generator units. A plant of this size would cost about $3,000,000 if built to-day. During the four summer months the permissible load on the generators would be reduced from full-load rating about 5 per cent, on the average, on account of the warm atmospheric conditions. In most stations it is either necessary or desirable to operate at rated full load during this period. In order to generate the full 30,000 kw. during the hot months it would, therefore, be necessary to do one of three things, (1) install air washers; (2) increase the size of the electrical end of the units, or (3) install a spare unit. For illustration it is sufficient to compare the first two. Each of the 10,000-kw. machines would require a washer of 40,000-cu.-ft.-per-minute (1120 cu.-m.-per-minute) capacity, and THE BOILER AND ENGINE ROOMS 91 the total cost of the tliree washers would be about $7,i30U. The fixed charges on this investment, including interest, taxes, insur- ance, maintenance and depreciation (taken at 15 per cent.), are Table I — Turuo-Alternator T^ad as a Function of Tncoinc-Aik Temperature ( — Temperature of Injjoing Air — ^ Load in Percenla^^e of Load De > > o - o o o — o o c c o Dollars ^ 1 1 ■9C -8C -70 -Ml -50 4C -^ i ,>>- \< t^' — ?« ?" ^^c 5-. cf/ / ^: : "■ >-■ w ?^ 1 A o; f \ 1 1 \ K 7P ^ w I 1 \ -80 -10 1 >/ 1 1 A \< // ! ' iri O ir> o ir> o in c> f^^ ro t\j fu — — 2 Dollars Cdpiicity in Kv.A. Cost of Washer and Duct inst<3l led Fig. 25 — Relation Between Kva. Rating, Amount of Cooling Air Re- quired pe:r Minute, Cost of Air Washer and Cost of Washer Installed Complete to blow several pounds of soot per minute into the intake and have the air at the generator inlet perfectly free from dust. There is a more or less widespread belief that the humidifying of the air increases its cooling capacity on the ground that wet air, on account of its higher specific heat, has greater heat-absorb- ing properties. The effect of this change in specific heat is negli- gible as far as heat absorption is concerned, because the weight of water vapor present even in saturated air is very small as com- pared with the weight of the air itself. The difference in the amount of heat absorbed by saturated air as compared with dry THE BOILER AND ENGINE ROOMS 95 air under a given set of conditions is not more than 1 or 2 per cent. o H K Ui u O o « PS o m H Pi < o D5 -^ O H <^ U <^ w o ;^. S o CO a 96 CUTTING CENTRAL STATION COSTS The precooling action of the air washer is, however, of import- ance. Assume a 12-500-kva. unit which requires 30,000 cu. ft. (850 cu. m.) of cooling air per minute and in which the losses amount to approximately 300 kw. at full load. The heat ab- sorbed per hour, assuming a final temperature of 100 deg. Fahr. (37.8 deg. C), neglecting the moisture in the air, will be as fol- lows : I. Air not precooled and entering the generator at 68 deg. Fahr., 0.24 X 0.07524 X 1,800,000 (100 — 68) = 1,040,000 B.t. u. 's per hour. II. Air originally at 68 deg. Fahr., but cooled in the washer to 53 deg. Fahr., 0.24 X 0.07788 X 1,800,000 (100 — 53) =1,580,- 000 B.t.u. 's per hour. In the first case, the losses absorbed amount to 1,040,000 B.t.u. 's per hour, or 305 kw. ; in the second to 1,580,000 B.t.u. 's per hour, or 463 kw. It may be assumed with fair accuracy that the losses are proportional to the squares of the currents ; therefore, I'^'/l^ == 463/305, or /g = 1.23/i. The terminal voltage is, of course, constant, hence the kilowatt output when the air is precooled will be theoretically 23 per cent greater than with air at the higher temperature. It is more probable, however, that in practice the gain under the conditions stated would amount to 15 per cent, although gains of 20 to 25 per cent have been realized even where the natural conditions were particularly adverse. The gain in generating capacity obtained by precooling the ventilating air is large, but is obtained by the expenditure of a comparatively small amount of money, as shown in Fig. 25. The use of the chart is illustrated by the following : Problem. — Given a 25,000-kva. generator, to find the amount of cooling air required, the cost of the air washer and the cost of the washer installed in place. Solution. — From the intersection of the vertical line through 25,000 kva. and the curve, run horizontally to the vertical scale. The required air is 58,000 cu. ft. (1640 cu. m.) per minute. Run- ning horizontally to the intersection with the first curve, read on the upper scale the cost of the air washer as $2,050. Running horizontally to the second curve, read on the lower scale $5,500 as the cost of the complete installation. An illustration of an air-washer installation used in connec- tion with a turbine plant is shown in Fig. 26. The air, which is THE BOILER AND ENGINE ROOMS 97 drawn through louvers and screens at tlie left, passes tlirough the washer and then through the generator, from which it is dis- charged direct to the forced-draft blowers in the boiler-house basement. This method of operation is employed during summer weather when it is desired to obtain the coolest air possible for the gen- erator. The discharge to the forced draft blowers of this quan- tity of heated air improves the boiler efficiency somewhat and maintains a lower turbine-room temperature. Under winter conditions the louver opening in the outside wall is closed by a rolling door and the air is drawn into the washer from the turbine room through the side door and discharged from the generator bypass through the sliding door provided for that purpose. Under these conditions the door into the boiler-room basement is closed. This method of recirculating the air from the turbine room keeps the room at a comfortable temperature. It also does away with the inconvenience of having a partial vacuum in the turbine room due to the removal of large quantities of air from an in- closed space. The washer to be purchased by the engineer should be of the size specified or recommended by the generator manufacturer, of the heaviest and most durable material, and able to cool the air to at least 85 per cent of the difference between the wet and dry bulbs. At the same time the air resistance through the washer should not exceed 0.375 in. (9.3 mm.) of water and the power consumption should be kept down to a minimum. CHARTING INSTRUCTIONS TO GET BETTER ECONOMIES Realizing that the over-all efficiency of its station will reach its maximum if the various generating units are combined to run at the most economical loads for the particular load condition en- countered, the Moline-Rock Island Manufacturing Company, Davenport, Iowa, has worked out a scheme for showing its plant operators how to combine the generators to get the best results. Tests were run •on the units to determine their efficiencies in terms of steam consumption at various loads within their ratings. While the results of these tests (Fig. 27) can be used by any one 98 CUTTING CENTRAL STATION COSTS having technical skill and judgment to determine the proper com- bination of machines to carry any load, the company desired to ?? ■D 17 § le £ '^ E 14 o ® 13 \n 12 11 \ \ \ \ r— \ I \ 1 \ \ \ \ \ \ ' 1 1 \ i \ \ \ u ht 1 -No. 7: 1 t Nab.. 1 1 -^ ». \ / y f y .^ N( ■>?■ '\ \ \ } / V y \\ In / / ^.^ \ K \ \ y 1 o \ J ^ A c\ 1 ^ ^ s' -— No.5^A ■ 1 -Nc i5-- V [^ ^ y' ~^^ ^ ■A ^ ■-^ ^ 1 ^ 1 . -H ^"i ^ P P ^ 1 < y~. — ... , ^ 1 1 1 1 1 1 IM 1 //V) Dro rruT D r ^' 1 1 |- '''\ 1 1 \ 1 320 280 240^ o o (X. r«-% C O. 1 7 \ \ i3.m ^ r II3M H. >- // r_ " • " — 1 — ^4-^ — '• — i— ^ 4-1 •v: ! \:T: — — _ . I2.M* «• 4 12 — -"i^" ^ ~^ - +jj-\ ■j - Rffi ;-^-i -\< ^- § ^ ^ 11000 *. .- 12 h^ -^ - - --j-f L^ fl -^ 1 — — '•'■ •- .//5L — n .^^ — ■ -'— — /-f/p M^ T = ^ i f M \ -^ ^^ S.«0 , 1 ' c; 11 T^'" \ 1 L 9.00* ^ — ~ Ti T '^ 1 ■ '— V " " - ^- \- V *■'•- /? ^ - y?^ r-TT r%- --V- '-^■ ^ -7 ;^ iOOO •» "1 /O .•to 11- /(9 XtA ^- - — — — l~ft ^ =^ "^^1 — "^ 1 ~ ■" ^ — - 1000 **• **~ //4 Y _, __ __ -/• /J 1 -Vli .^- _ .. - '*\ \- ,. %JM »'"•-. /P" ^ _i-. _i ._ —if u_ t_ -N _. «.000 _ J f^- _. _ /■-■ ' t ___ n ^ b.MO V \ 7"v tl V ^ 100« "•TfAfl \ / Jul / \ \ *.bOO V 1 loci/ , B 1*00 1 \- w — -i _ \ -_ — 1 — ^ 1 _ _ SJM iS s T"-:3^ — 7^ — rv — ^ ' — ~~ t^ i<7 V/s? rr- / \ 2.000 iVtfP .'..'., ■>^/a;>::- ■'- :■• •r^-. -. .... i'.i ::'i £4 S.'tiZ ~~ ^ ~ -■!:^ — ¥i(ff^ — L..^._., -l^'fc -r -._ -^ _.__ — — j X: iM 1 _ _^— r— ',.1 17. ■ I ■--I — ' -\ aCf. 4f$4 *54 »< 104 554 854 l»« »; /^r iP.- »4 /5i ?55 u,- ^M^h-IJt- /"flS Fig. 28 — Portion of Log Sheet Used by Davenport (Iowa) Company Curves Nos. 1 and 5 represent the water rates and total steam consump- tion of a 3000-kw. turbine at 100 per cent power factor and deg. super- heat; Nos. 2 and 6 represent the corresponding quantities for a 6000-kw. turbine at 90 per cent power factor and 100 deg. superheat; Nos. 3 and 7, the values for a 10,000-kw. turbine at 95 per cent power factor and 100 deg. superheat, and Nos. 4 and 8, the values for a 20,000-kva. turbine at 80 per cent power factor and 125 deg. superheat. THE BOILER AND ENGINE ROOMS 99 present the information in such form that any operator, regard- less of his technical judgment, may determine instantly what to do under ordinary conditions. Consequently all of the more common operating conditions that are likely to arise are listed in a table like that shown herewith, giving the combinations of units to use and the loads on which each unit shall be operated. With this table the operator needs to do no figuring and does not even have to consult the curve sheet. As a detail in connection with the actual making of these charts and curves, it is interesting to observe that the tabulated data arc blue-printed on separate sheets and then pasted on the curve sheet. This saves time in changing the tracings as well as the curve sheets when changes in the operating schedule are neces- sary. Chart of Turbines to Operate at Different Loads to Relieve Operator FROM Necessity of Relying on His Own Judgment K\v. Load per Respective K\v. Load Units in Service Unit Up to 1750 3,000 Total load 1,750-4,500 4,500-8,000 10,000 12,000 14,000 16,000 18,000 20,000 22,800 6,000 10,0001 10,000 6,000 Total load Total load 8,000- 9,000 2,000- 1,000 10,000 6,000 0,000- 8,000 3,000- 4,000 10,000 6,000 10,000- 9,000 4,000- 5,000 10.000 6,000 3,000 10,500-11,000 5,300- 4,800 200 10,000 6,000 3,000 11,500-11,000 6,300- 6,800 200 10,000 6,000 3,000 12,000 7,200 800 10,000 6,000 3,000 12,000 7,200 3,600 1 If two units are used run 6,000 at 200 kw. 100 CUTTING CENTRAL STATION COSTS Of next importance to providing proper instructions for han- dling various loads is the matter of seeing that the instructions are carried out intelligently. The officers of the company keep in touch with this situation through a system of daily power- house reports. In addition to the usual data asked for on daily power-house reports, these reports call for the load curves from each of the plants, the total load curve and a graphical statement of the hours of operation and of each turbine and boiler unit. A part of one of these reports is reproduced herewith. The hor- izontal lines drawn through the load curves are the feature of the report. Each line, it may be observed, is opposite the designa- tion of a turbine or boiler unit at the right margin of the page. The length and position of these lines indicate what machines were used at each hour, and also show in definite relation to the load curve how accurately instructions have been carried out. The lines used to show boiler operation also show whether the boiler was steaming or was banked. B. J. Denman, president of the Moline-Rock Island Manu- facturing Company, is a strong believer in the value of this method of charting operating methods. He has applied it in the past to other plants under his direction, and each time im- proved economy has resulted. HOW TO REDUCE COST OF STATION REGULATOR Conditions with the Dayton (Ohio) Power & Light Company made it seem necessary to regulate the voltage on circuits sup- plying station lighting in the new power house at Miller 's Ford. To keep from buying a high-voltage regulator to operate at the generator potential of 6600 volts the scheme of connections illus- trated here was worked out. From the 6600-volt bus these cir- cuits were taken through the 200-kva., 6600/230 and 115-volt transformer which fed all station lighting circuits. In the out- side lines of the three-wire secondary of this unit was connected a series boosting transformer with a ratio of ten to one, the high- voltage winding being designed for 230 volts and the low voltage for a total of 23 volts, 11.5 volts in each half. The high-voltage winding of the boosting transformer receives from volt to 230 volts from one winding of a low voltage one-to-one ratio induc- tion regulator, the other winding of the regulator being energized THE BOILER AND ENGINE ROOMS 101 from tlie outside lines of the secondaries of the main 200-kva. transformer. Connections to the contact-making voltmeter as eeoo-\^ Bus .W AV». eeoa/F30y Main Lighting Transformer Neutral Series Boosting Transformer .Ratio?iO-V todS'V 11.5 V •a5M5MV 115 V ? — > /1.5 V 210 V — - 250 y Induction Regulator Ratio II 115 V for Station Lighting Contact Malting Voltmeter Fig. 29 — Eegulator Arrangements Made to Avoid Buying High-Voltage Unit shown completed the job. The unit is now operating satisfac- torily. TRACK SCALES SAVE THEIR COST IN VERY SHORT TIME E. S. Hig'ht of the Illinois Traction System, Peoria, 111., which operates light and power properties in many cities in the Middle West, is a firm believer in the value of track scales for central- station companies. Several properties of this company have bought track scales and installed them at their plants. When a car of coal is received it is weighed before being dumped. If the track scales show that the car contains only 88,000 lb. (40,000 kg.) of coal, while the invoice shows that it contains 100,000 lb. (45,000 kg.), the central-station company pays for only 88,000 lb. (40,000 kg.) of coal. The money which it has saved through this process, Mr, Hight says, will soon pay the cost of the scales. When this view was recently presented before the Iowa Section, National Electric Light Association, the question arose as to whether this plan should be employed where the contract which the central-station company had with its coal company specified 102 CUTTING CENTRAL STATION COSTS that the coal was to be paid for at "mine weight." Mr. Ilig-ht expressed the opinion that this provision in the contract carried little weight if the central-station company through the use of track scales showed that car weights were short. He said further that he believes no coal company would go into court with a case where accurate records kept by central-station companies showed that the weight of cars at the central station was less than it was represented to be at the mine. TEAM SYSTEM IS THOUGHT TO BE BEST LABOR SOLUTION Labor conditions affecting public utilities are as difficult at Youngstown, Ohio, as at any point in the country, according to H. W. Bromley, engineer of power production for the Mahoning & Shenango Railway & Light Company. As a result of this the company has come to the policy of paying wages as high as any of the neighboring industries, including the steel mills. Com- mon labor, which two years ago was paid 17.5 cents an hour, is now getting 54 cents an hour. Watch engineers are being paid $173.50 per month for nine-hour-a-day shifts ; switchboard men receive 52 cents an hour and work nine hours; oilers and water tenders are paid 45 cents and 51 cents an hour respectively, and foremen are paid from 45 cents to 48 cents an hour. Besides be- ing expensive, this labor is difficult to handle, and constant fric- tion arises. Bonus systems have been tried, but without success. The lat- est plan, and the one which seems to Mr. Bromley to be destined to give the best results, is one which he calls the team system. With this plan a foreman paid 70 cents an hour is placed in charge of five or six men. This unit is called a team. The fore- man is held responsible for the quantity and quality of work done by the team as well as for destruction of material by its members. The teams are usually chosen so that all of the men in each unit, including the foreman, are of the same nationality. The real bosses of the job then talk to the foremen, but never to the men. This plan gives the foreman a good opportunity to keep in close touch with all members of his team and to bring out their best efforts. Of all the groups employed under this system negroes are said to have accomplished the best results. THE BOILER AND ENGINE ROOMS 103 A PLACE FOR GAS ENGINES In many electric service systems there are frequency changers or synchronous condensers at various points that miprht be util- ized to help carry increased loads without much additional invest- ment, says Henry M, Trench, a construction engineer. Since these units are usually situated at the tie-in points between sys- tems or at centers of distribution, the conditions are almost ideal for their operation as generators. To permit this little additional equipment is needed besides some internal-combustion engines (gas or oil, depending on which is more convenient to use) to drive the units. Where such machines are installed a clutch or other mechanical connection may be inserted between them and the internal-com- bustion engine so that they may be engaged or disengaged as con- ditions require. With this arrangement the units may be used for their original purpose or as generators whenever desired. The engine attached to a motor-generator should be rated at the combined capacities of the motor and generator so that both may be driven as generators. Starting of such reserve plants could be made automatic if desired, since power would always be avail- able to start the outfits from the generator end. SECTION II THE SYSTEM ECONOMY IN ELECTRICAL DISTRIBUTION In order to get the maximum use from existing apparatus greater effort must be made to study the losses in distribution and to reduce them by the best means, writes W. B. Stelzner, "When automatic voltage regulators are used on lighting feeders, for instance, it may be possible to open the primary circuits during the light load period and thus save 75 per cent of the iron loss. It is generally known if the primary lines of a distribution system are too small an excessive copper loss results, but it is not so well understood that if the voltage at the load is low the power is correspondingly decreased and a definite loss of revenue occurs. Larger conductors are thus required. In the case of low-tension circuits, however, line losses may often be reduced and the service improved by changing the transformer locations. Another seri- ous obstacle to economical distribution is low power factor at the load, which causes high line losses and seriously limits the capac- ity of the wires. This condition may usually be attributed to the operation of induction motors on the system at only partial load, and is obviously best corrected by rearrangement of the motors or if this is not feasible by the use of synchronous motors. An analysis of the losses on the lines of a company of medium size was recently made and some of the results are here reviewed in order to show the economic importance of these losses in the distribution of electricity. The losses that will be discussed are : the high-tension-line copper loss, the low-tension-line copper loss, the induction regulator losses and the transformer losses. The copper losses will apply to the conditions obtaining for the aver- age winter load. The system studied includes a generating station connected by four lines to a substation from which emanate three lighting feed- ers and one power feeder. These feeders are equipped with sin- 104 THE SYSTEM 105 gle-phase regulators and supply current at approximately 2400 volts. A synchronous converter also supplies a railway load from the substation. High-Tension-Line Copper Loss. The high-tension-line cop- per loss is given in Fig. 30, which shows the condition existing in one of the lighting feeders. The curves show this loss to be 98 kw.-hr. for a twenty-four-hour period, or 16.6 per cent of the IRD j V 140- f \ 130 - 1 1 \ 120 " \ t 1 A \ / '^ \, 1 '"lOO- •1- \ \ ^\ ^\ V *" 90 ^\ \ C ^ ? ^° A-L ppa\ .loss OSS -f O (0 - B-L roi n ^e Tier S' .- 60 - low volta C-Treinsforr - copper loi - - ^ 60- 40 -- c ron losses 9e(^ulafor opper loss -- — / — f^"* .0 / f\ \ / ^ \ '° / % ^ r. \ J - J >4 •£3 K ^ ^ 8 10 12 P.M. 1300 1800 1700 1600 1500 1400 ;i300 *"I200 c illOO o -1000 ^ 900 600 ^100.700 o 90 600 V i 60 600 400 1 1 1 1 1 1 1 1 1 r^o* r — A- Totcfl input to tie lines — B- Total input to station 2 — A-B-Tie line losses — B-C- Feeder line and _ transformer losses _ C- Output to low-tension AC fines and input to synchr- onous converter ~ A-C- Total hicjii-tension — losses — D- Efficiency 1 \ 1 n 1 ^c 1 \ 11 11 1 111 111 1 1 \ I / ^ 1 / \ y \\ \ / *^ ^ \ ^ \ \\ / \ / ^V ' 1 V / Y( // N / ' ^ s^ ■n y s. \ — V. / K / / s / "S — — -" i 8 10 A.M. 12 4 6 P.M. 6 10 Figs. 30 and 31 — Loss Curves for Single-Phase Feeder and Efficiency OF High-Tension System Maximum copper loss occurs at peak load and may thus limit rating of line. Iron losses are ever present, however. energy sold in the same time. This large line loss is accompanied by an excessive pressure drop with the result that the pressure at the load is below normal and a direct loss in the sale of energy ensues. When the load current is 51 amp., the regulator reaches the position of maximum boost and any increase in load current produces a fall of voltage, entailing a loss of revenue. In this case the obvious remedy is to increase the size of wire in order to reduce the line drop sufficiently to permit the induc- tion regulator to hold the voltage up to normal. The loss of 106 CUTTING CENTRAL STATION COSTS energy may be calculated at the rate of 7 cents per kilowatt-hour, assuming that the added cost of supplying this energy would be small. As will be noticed, the line copper loss is appreciable only between 5 and 10 o'clock in the evening. Although this loss occurs at the peak load, a possible minimum value for the loss, the cost of coal, might be 0.5 cent per kilowatt-hour. Using pre-war prices for material and labor and an annual charge of 10 per cent for interest, depreciation, insurance and taxes, the saving by re- placing the No. 6 wire used with No. 2 is as follows : No. 6 B. & S. Wire No. 2 B. & S. Wire Cost of wire as installed to Cost of wire $602.00 point a, Fig. 5 $239.00 Changing wires 80.00 $682.00 Credit for removed wire. . . . 75.00 Cost of change $607.00 24-hr. capital charge .00 .17 24-hr. cost of line loss .49 .19 24-hr. loss due to low voltage 3.36 .00 Total 24-hr. change $3.91 $0.36 The calculations indicating the economy resulting from the selection of a No. 2 wire for this circuit are summarized in the following tabulation : Wire Size, B. & S. Gage 4 2 1/0 2/0 3/0 4/0 Additional capital required for change to above wire size . . $385 $607 $985 $1,235 $1,545 $1,955 Total twenty-four-hour charge $0.40 $0.36 $0.40 $0.43 $0.49 $0.60 The No. 2 wire carries the smallest charge and the capital expen- diture required in its installation will be recovered within one year's time owing to the decrease in operating costs. The econ- omy resulting from the substitution of the larger wire is very evident. Low-Tension-Line Copper Loss. The low-tension-line drop is probably the most important element in maintaining a high standard of service. This is apparent when it is considered that by means of voltage and power-factor regulators the pres- sure of the high-tension lines can be controlled. With a well- designed system and under efficient operation these regulators give practically constant voltage at the distributing centers. Es- THE SYSTEM 107 pecially is this true when lighting feeders are maintained separate from the power feeders. Such apparatus is not used on the low- tension lines and the regulation at the loads is therefore deter- mined almost altogether by the low-tension-line drop. The line losses in the low-tension circuit are indicated in Fig. 1000 «n 800 o 600 400 200 n y y V S ^ y^ \ V, ^* ^ ^^ S 'V \. ^ "^ ^ ^ N ^ \ s. A-Tranformer af ''a"* ^ ■v^ S 'v e 7 a R. M. Fig. 32 — Low-Tension-Line Loss 10 Curve A for the circuit shown in Fig. 34 with transformer at a; curve B with transformer at c. 32. These data give the copper loss in the line wires and service leads and show the influence on the losses of the design of the circuit. The information may also be presented as follows : Curve A Curve B Transformer size (kva.) 20 20 Energy sold (kw.-hr.) 90.7 90.7 Line loss (kw.-hr.) 3.94 2.39 Per cent lost 4.2 2.6 A comparison of curves A and B indicates which is the most economical location for the transformer feed-in point. This is a most important consideration both with regard to the losses and to the regulation at the loads. The cost of moving this trans- former to the position indicated would be $5.50, a sum fully war- ranted in view of the improvement in losses and regulation. A further change that might be warranted would be to change the size of wires ab and Z)c. In some cases other considerations may govern the selection of the transformer location, and position a. Fig. 34 may be chosen. In this event the change in wire sizes must be made or the circuit may be sectionalized and another transformer installed. Power Factor. The powder factor of a circuit depends not 108 CUTTING CENTRAL STATION COSTS only upon its characteristics but those of the apparatus connected to it. To transmit 100 kw. at 2400 volts single-phase would re- quire a line current of 41.6 amp. if the power factor is unity, and a current of 52 amp. if the power factor is 0.80. Due to this increased current at reduced power factor, the copper loss in apparatus and lines is increased in proportion to the square of the decrease in the power factor. Low power factors, therefore, mean greater losses, lower capacity and decreased economy in distribution. The power factor of a circuit may be changed by a rearrangement of motors and loads, so that all induction motors will be operating under approximately normal load conditions, or synchronous machines may be used of sufficient rating to con- trol the power factor of the circuit. For the circuits involved in this study the power factor of the lighting feeders averaged 0.92 at peak load and 0.42 at no load. The power feeder, owing to lightly loaded induction motors and transformers, had an average power factor of 0.52. The power factor of the tie lines was usually kept above 0.90 by over-excita- tion of the synchronous machine supplying the railway load. Fig. 33 gives the loss in the tie lines for two loads, a day load and a night load, and shows how this loss would vary with the power factor. Suppose an induction motor-generator set were used in the substation and that this should result in a tie-line power factor of 0.85 for the night load and 0.70 for the day load. Then results would be as follows : Loss Due to Resulting Reduced Actual Loss Assumed Loss Power Factor Time ( Kw. ) Powder Factor ( Kw. ) ( Kw. ) 7 p. m 108 0.85 141 33 10 a. m 66 0.70 117 51 The reduction in line loss by power-factor correction, with its accompanying effects on the pressure regulation at the substation and on the capacity of the tie lines, measures the economic value of power-factor control and its influence in the selection of power equipment. Voltage Regulation. Pressure regulation is involved in all distribution problems and it is an important factor in electric service. Good regulation means minimum losses and maximum sale of energy. By separating the lighting and the power loads and supplying THE SYSTEM 109 them by different feeders, as is done in the system studied, indi- vidual control of each is possible and the best regulation may be secured. To accomplish this automatic voltage regulators are required for each circuit. The fluctuating power loads produce power factor and current variations in the tie lines, and these two effects combined with 120 §■100 o S 80 i- 60 / / ^ y .?• ^A ^ r y ^ X y ^ y y' ^ \ i( 5>1 ^ ^ .--' ^^ 100 95 90 85 bO 75 70 Per Cent. Power Factor Fig. 33 — Variation ob^ Tie-Line Lo.ss with Power Factor variations in the generated voltage determine the fluctuations of the pressure at the substation bus. This pressure may be con- trolled by the use of an automatic voltage regulator in connec- tion with the synchronous machine in the substation, as in this way the power factor may be held constant. A similar regulator, if required, installed at the power station would control the pres- sure generated there. Induction Regulator Losses. The loss in energy sold due to low voltage at the load, as shown by Fig. 30, is caused by resist- ance of the line. The loss is kept as low as that given by means of the boosting action of the induction regulator, increasing the phase pressure from 2400 to 2600 volts. The influence of the regulator in controlling this loss is determined as follows : Energy delivered to the circuit as installed (kw.-hr.) 757. S Energy that would be delivered without regulator (kw.-hr.) 62(5.0 Difference during the period of twenty-four hours (kw.-hr.) 131.8 This indicates the decided usefulness of the regulator even with- out considering its chief function of improving regulation. 110 CUTTING CENTRAL STATION COSTS The regulator which was under consideration was rated at 11.5 kw., 2200 volts, 50-amp. secondary. It was an old design with a tested iron loss of 400 watts and a copper loss at rated load of 187 watts. The high iron loss is partly due to the fact that it is subjected to a pressure 9.1 per cent in excess of that for which it 20 16 12 > i. E D z i''f ans .erf former a fob N?2 wire Transform at a. er i ]^ c Balance of circuif N° 6 k.--(" ; « I \ wire b \ l" c \ \ 1 I a .TRANSFORflER \ \ ; \ \ \ 1 1 1 1 1 \ \ 1 \ \ 1 \ A / \ \ \ \\ \ 1 A A / \ ( \ i\ / / J \ y ./ s V / \ / v/ V \ V \ \ 1 -J \ J \ 236 232 228 224 S e r V i c e 2I& 214 210 220 Voltage Fig. 34 — Voltage at Service Connections Full line shows number of services receiving a given voltage at peak load. Dotted line shows the improvement resulting from moving transformer from a to c. was designed. The exciting current was found to be 2 amp. For a regulator of modern design the iron loss would be about 160 watts and the exciting current 1.89 amp. A comparison of the losses for a year 's time gives the following results : Old Regulator New Regulator Annual cost of iron loss $17.51 $6.57 Annual cost of copper loss 2.61 4.53 Total annual loss $20.12 $11.10 or an annual saving in losses of $9.02 in favor of the modern de- sign. This saving alone, however, would not justify the in- creased capital expenditure required to make the change. The greatest economy in this case would be realized by install- ing switches in the shunt coils of the regulators so they may be disconnected during the nineteen hours per day of light or no load. This would result in an annual saving in iron loss of $13.75 per phase or $41.25 per feeder. Assuming a three-pole switch, installed, to cost $75 and an annual charge of 13 per cent, THE SYSTEM 111 we have an annual charge of $9.75 on the switch. The net sav- ing, if the switch is used, amounts to $31.50 per feeder per year. The iron loss of all transformers on one circuit amounts to 1.2 kw. At a cost of 0.5 cent per kilowatt-hour the annual cost of this loss is $52.60. With rated voltage at each transformer and with transformers of modern design the annual cost of the iron loss would be $-1:7.80, a saving of $4.80 per year. Obviously this sav- ing alone would not justify the replacement of these transformers with others of the proper voltage rating. Summary of Losses. In order to show the relative magni- tude of the losses as studied, the following table applying to one circuit is given for the twenty-four-hour period considered. Transformer iron loss (kw.-lir.) 28.8 Regulator iron loss (kw.-lir.) 9.6 Total iron loss (kw.-lir.) 38.4 Per cent of total loss 20 Transformer copper loss (kw.-hr.) 12.5 Regulator copper loss (kw.-hr.) 1.4 Line copper loss (kw.-lir.) 08.0 Total (kw.-hr.) 111.9 Per cent of total losses 50 Loss due to low voltage (kw.-hr.) 48.0 Per cent of total loss 24 Total loss (kw.-hr.) 198.3 Total input ( kw.-hr. ) 788.4 Total output to low-tension lines (kw.-hr.) 590.0 All-day efficiency, per cent 75 The total losses in the high-tension system are as follows : Kw.-hr. Energy to tie lines 21 ,440 Energy to bus at substation 20,300 Loss in tie lines 1,080 Loss in feeders, regulators and transformers 1,114 Total loss 2,194 Conclusions. Knowledge of the actual losses and their dis- tribution over the system is essential to the most economical operation. Such data show just where more copper is needed, where copper may be removed, where to install regulators and power-factor-correcting devices, the most economical location of transformers, etc. In other words, a knowledge of the distribu- 112 CUTTING CENTRAL STATION COSTS tion losses is necessary for the most effective use of the system or the production of maximum service at a minimum cost. The line copper loss, since it varies with the square of the load current, is likely to be serious. The gradual growth in load may result in large line losses or changes in the distribution of the load may result in idle copper. A survey of the losses reveals these conditions and leads to their correction. The iron losses are kept low on this system by reason of the fact that the transformers are so spaced as to supply rather large areas. In this way larger as well as fewer transformers are used with a resulting reduction of iron losses and exciting current. This practice also results in a lower investment in transformers. Another advantage lies in the fact that by supplying the larger area a reduction in transformer rating is possible because of the diversity factor of the connected load. In some cases, however, these economies may be more than offset by the losses in the low- tension lines. Economies can be obtained by using larger trans- formers and increasing the distance between them when such a policy is consistent with the investment carried in the low- tension mains. Power-factor correction on lines carrs'ing loads of low inherent power factor results in a material saving in line loss and line capacity and a decided improvement in regulation. The value of a study of the losses encountered in the distribu- tion of electricity is made apparent by considering the fact that the ultimate cost of the product depends on the efficiency of the system. High efficiency, though a desirable attribute, cannot always be fully realized if the system is to have its greatest value. Low capital cost is essential to low production cost and low cap- ital costs are influenced by losses as well as by diversity, load factor, available funds, etc. On the other hand, a mistaken econ- omy in capital costs may act to seriously impede the development of the system. While no system can be laid down as commer- cially complete, the engineer must look, although it may be far into the future, to what would probably be the demand if the whole energy consumption of the district were supplied elec- trically. The rapid growth in the load so often experienced illustrates the necessity for a rather generous attitude on the part of the public toward the utility in order that this increase may be prop- THE SYSTEM 113 erly taken care of and the best interest of both public and com- pany conserved. TREND OF PRACTICE IN OVERHEAD DISTRIBUTION In keeping with the spirit of the times, the transmission and distribution committee of the Ohio Electric Light Association has pointed out that the most important factor in distribution systems is the economical and efficient use of all apparatus and materials. This it is believed, would lead to a standardization of all materials. Usually a distribution system grows by the ad- dition of transformers and secondaries. Then as the system ex- pands it generally requires complete revision. The most notice- able condition is the great number of small transformers which have been installed. These should be replaced by several large transformers, of which the advantages are enumerated below : 1. The investment in transformers is less because of the smaller cost per kva. of the larger transformer. 2. The core loss is less and therefore the efficiency is greater. 3. The number of lightning arresters is reduced. 4. The transformer capacity might be reduced because of the greater diversity of load which occurs with the larger number of consumers supplied from a single transformer. 5. Transformers should be installed about 1700 ft. (518 m.) apart in residence sections to insure the economical use of a distribution system. The secondary system should be rebuilt, using three-wire 230- volt circuits for all street mains. Great care must be exercised to provide a balanced condition of the load. The neutral wire in a balanced system may be two sizes smaller than the outside wires. The voltage drop of a balanced three-wire system is one- fourth that of a two-wire system, other conditions remaining the same in both systems. ECONOMY OF WATER EFFECTED BY INTER- CONNECTION It is well known that it is a business necessity for every elec- tric power cdmpany to give special stud}^ to the finding of possible economies. In order that the greatest amount of conservation be 114 CUTTING CENTBAL STATION COSTS possible, it is essential, writes R, H. Halpenny, Electrical Engi- neer, Southern Sierras Power Company, that companies operat- ing in the same or adjacent territory make a study of load con- ditions peculiar to each with a view toward determining what possible economical advantage is to be had by an interconnection of the systems. There are valleys in the daily load curve of the Nevada-California Power Company that allow the plants operat- ing on that system to deliver 6000 kva. to the Southern Sierras Power Company system through the three-phase tie-in trans- former, and to do this without the use of any greater quantity of water than that required by the Southern Sierras plants oper- ating on the same stream. When two or more companies make use of both hydro-electric and steam-electric generating plants it is often possible to profit by the dissimilarity in the load curves of each company to effect a saving in fuel by the more advantageous use of available excess hydro power resulting from an interconnection of the systems. By such interconnections of their systems various groups of power companies in this country have made possible the use of great quantities of coal and fuel oil for other purposes. A typical in- terconnected group is that of southern California. The magni- tude of the resultant fuel conservation and the extensive char- acter of the interconnection have been presented to the readers of the Electrical World in the interesting article of R. J. C. "Wood in the issue of Aug. 24, 1918. It is not the intention here to deal with the subject of fuel conservation as accomplished by the tying together of a number of large systems. It is proposed instead to describe an intercon- nection of two electrical systems that makes possible the greatest economy in the use of the same storage water by certain of the generating plants of both systems. On a small stream on the eastern slope of the Sierra Nevada mountains the Nevada- California Power Company developed storage facilities and installed three hydroelectric plants during the period 1905 to 1908. Typical of many streams in the Sierra Nevada range this one, known as Bishop Creek, is served by a watershed of considerable area and has a rapid fall, dropping more than a mile (1.6 km.) in 14 miles (22 km.) of length. The area comprising the watershed is about 39 sq. miles (10,000 hec- tares) in extent and is made up of three separate run-off areas THE SYSTEM 115 from which issue the North, IMiddle and South Forks of the creek. Natural storage sites on the south and middle branches of the creek were utilized, and by the construction of dams a total storage capacity of 21,000 acre-feet (25,800,000 cu.m.) was de- veloped. The natural flow of the stream varies from 20 second-feet (0.6 ^'OALV. IRON PIPE ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^??^^^^^ Fig. 35 — Cross Section of Outdoor Control Substation at Junction of Inter-Connected Lines cu.m. per second) to 700 second-feet (20 cu.m. per second) at dif- ferent seasons of the 3'ear, and it is evident from this that storage is essential for the continuous operation of generating plants; in fact, during four months in the year it is necessary to depend on storage water to a very large extent. Two transmission lines were built into Nevada for the purpose of serving the mining district in and around Goldfield, Tonopah, Manhattan and other southern Nevada mining towns. This transmission sj-stem, with a mileage of 270 miles (430 km.), is of wood-pole construction and is operated at 55,000 volts ''Y, " with neutral solidly grounded at generating stations and substations. Systems Interconnected. During the years 1912-1913 the Southern Sierras Power Company constructed two plants on Bishop Creek, making a total of five plants on the one stream. The erection of a double-circuit steel-tower line 239 miles (385 km.) in length and terminating to the south of San Bernardino, Cal., made possible the transmission of this additional power to an entirely different section of country from that served by the 116 CUTTING CENTRAL STATION COSTS Nevada- California Power Company, and permitted a more com- plete utilization of the power development. The design of the tower line is such that operation at 140,000 volts ''Y" is possible, although a transmission voltage of 87,000 volts was decided upon as best suited for the period during which a market for the power was being developed. At the time the line was put into service certain conditions made it desirable to ope- rate it for a time at 55,000 volts and all transformers were accord- ingly provided with a 55,000-volt tap. By reason of the capacity in synchronous units available at the southern end of the line it has been possible to operate the line up to the present time at 55,000 volts with reasonably good voltage regulation. This syn- chronous capacity consists of generating units in the reserve steam plant at San Bernardino and synchronous condenser and frequency-changer sets at the end of some of the more important feeders leaving the San Bernardino station, making in all over 20,000 kva. capacity available for regulating purposes. Since the Southern Sierras system has been operated at 55,000 volts delta and the Nevada-California system at 55,000 volts ^'Y, " with grounded neutral, it was not considered advisable to operate the two systems as one because of the severe strain that would be imposed on the transformers of the ''Y" system by a grounded condition of one of the line conductors, owing to the delta-con- nected transformers of the plants on the other system. In emer- gencies it has been necessary to switch one of the "Y"-connected plants to the delta-connected system, but this operating condition has been avoided as much as possible for the reason that a heavy ground on several occasions put one or more of the ''Y"-con- nected transformers out of commission if the latter were operat- ing on the delta system at the time. It has already been stated that there are five plants on Bishop Creek. These plants are known as Nos. 2, 3, 4, 5 and 6, number- ing down-stream. The wheels at No. 2 plant discharge into the intake of No. 3, which plant in turn discharges into the intake of plant No. 4, and in this way the water is not allowed to seek the natural channel or creek bed from the time it enters No. 2 intake until it is discharged from the tailrace of plant No. 6, from which point it is given over to irrigating purposes. It will be evident from the foregoing that the greatest economy would result from the operation of the five plants in such a man- THE SYSTEM 117 ner that all the water passing through the wheels of one plant would in turn pass through each of the other plants. This is a condition that it is impossible to maintain with limited forebay capacity and varying loads on the different plants. The load curve of the Nevada-California Power Company systems differs materially from that of the Southern Sierras Power Company, and as a result the load demands on the individual plants do not occur at the same periods of the day. The load on the latter system has grown so rapidly that in spite of the addition of the recently completed Rush Creek plant with a capacity of 10,000 kw. it is necessary to make use of the steam reserve plant to handle the peak load. This condition makes it particularly de- sirable to have some means of connecting the plants operating on the two systems so that any excess capacity of the one group could be utilized by the other system, at the same time allowing Data on Bishop Creek Plants of Interconnected Systems Capacity, Eleva- Static Effective Kw. per Kw. tion, Ft. Head, Ft. Head. Ft. Sec.-Ft. Plant No. 2 6,000 7,100 938 850 55 Plant No. 3 6,000 6,280 814 725 45 Plant No. 4 6,000 5,156 1,180 1,000 62 Plant No. 5 1,500 4,728 438 350 22 Plant No. 6 2,000 4,461 280 220 13 each plant to operate at a capacity determined by the amount of w^ater passing through Plant No. 2, the plant furthest up stream. On account of the undesirable condition resulting from a direct tying together of the two systems it was decided to connect the two by means of transformers, this being all the more necessary because of the fact that the voltage of the Southern Sierras sj^s- tem is to be raised to 87,000 volts within a few months. A three- phase, 6000-kva., 87,000-140,000/55,000-volt C'Y") General Electric transformer was recently installed for the purpose of tying the system together, it being the intention to install a sec- ond unit of the same capacity in the near future. Location and Construction of Control Station. At a point near Plant No. 5 is the northern terminal of the tower line re- ferred to above^ and it is to this point that it is proposed to bring the lines from all of the hydroelectric plants in that district, mak- ing it a control switching station. This center is known as the control station, and it was the natural location for the installation of tie-in transformer equipment. 118 CUTTING CENTRAL STATION COSTS Plans for this station provide for two distinct parts, one to operate at 55,000 volts ''Y" and the other at 87,0000 volts delta or 140,000 volts ''Y." The 55,000-volt section has been partly completed, and a brief description will be given. The natural slope of the ground in that locality made it advisable to level off the required area in terraces, and these terraces form a natural division for the two parts of the station. On the upper terrace are the 55,000-volt bus structure and three-phase transformer. Fig. 35 shows a cross section of the station and arrangement of equipment. Unit-type construction has been used, as is the prac- tice of this company in building all of the more important sta- tions. Latticed-steel colum::s form the upright members of the structure, while 2-in. (5-cm.) iron pipe serves as horizontal sup- ports for the bus insulators and disconnecting switches. Each set of four posts forming one of the structural units is tied to- gether wdth light fabricated beams, which also carr^^ the pipe supports of the disconnecting switches. The bus is made of 1-in. (2. 5-cm.) galvanized-iron pipe with -/i-in. (1.8-cm.) iron pipe ris- ers from disconnecting switches to bus. All of the pipe and steel frame is galvanized. Plans for the completed station provide for two oil switches on each line, so that the lines can be readily transferred to either bus at will. These switches are equipped with remote control ; in fact, all of the switches at this station, in both the 55,000-volt and the 87,000-volt sections, will be operated from a 110-volt di- rect-current bus supplied by storage battery. The condition of the market at the present time as regards structural steel and electrical construction material has delayed the beginning of work on the new 87,000-volt section of the sta- tion. For the present the 87,000-volt lines will be connected to the 87,000-volt single bus of the older portion of the station. A temporary line on wooden poles will serve to connect this bus to the 6000-kva. transformer. Saving Resulting from Interconnection. The installation of this transformer and the erection of the 55,000-volt section of the station were pushed as rapidly as possible in order to antici- pate the seasonal increase of load in August and the months fol- lowing on the system of the Southern Sierras Power Company. This accounts for the incomplete condition of that part of the station just installed, but does not decrease in any way the gain THE SYSTEM 119 iu available power that the installation has made possible. The water required by the Southern Sierras company is thus used by the Nevada- California company to generate additional energy above its own load requirements, this excess energy being deliv- ered to the former company through the 6000-kva. transformer installed for the purpose. The direct result of this is a saving in fuel oil that would otherwise have to be used in order to make up the power deficit on the Southern Sierras Power Com- pany system. An additional advantage resulting from the inter- Matebial Requujed for Six-Circuit Structure Seven structural units. Seventy-two GO,000-volt disconnecting switches. Twelve three-pole remote-controlled 60,000-volt outdoor-type oil switches. Eighteen dead-end fittings. Eighteen l^-in. guy thimbles. 150 pin-type insulators and top clamps (for bus supports). 1,400 ft. %-in. galvanized-iron pipe (for bus conductor). 550 ft, 1-in. galvanized-iron pipe (for bus conductor). 300 ft. li/4-in. galvanized-iron pipe (disconnecting switch supports). 1,750 ft. 2-in. galvanized-iron pipe (supports). 228" clamp tees. Thirty clamp crosses. 156 high-tension cast pins. 112 U-bolts. Sixty pipe caps. connection is that both s^^stems have practically acquired 6000 kva. or reserve capacity against the possible temporary loss of a generating unit or plant. The mileage of the already extensive interconnected system of the southern California companies has also been increased by the addition of the Nevada-California system, which heretofore has had no physical connection with the group. The importance of this additional reserve capacity to all of the companies in the interconnected group has already been demonstrated. On the occasion of the loss of a large generating unit by one of the com- panies, the completion of the installation just described made it possible for some 5000 kw. to 6000 kw. to be delivered contin- uously to the compan}^ which was in need of assistance, and in this manner a serious power shortage was averted. The installation of a large transformer in a locality removed some distance from the railway presented some difficulties in transportation and handling. The core of the 6000-kva. unit 120 CUTTING CENTRAL STATION COSTS weighed something more than 36,000 lb. (16,000 kg.), and in order that this piece could be hauled 15 miles (24 km.) over roads that are in only fair condition it was necessary to make a special rig so that the load could be distributed on two wagons, since no wagon in that district was capable of carrying the entire load. In order to keep the center of gravity as low as possible the core was slung between two trussed beams. These beams were made up of cedar poles and two sawed timbers that were fortunately available. The wagons were trailers that had been used for tan- dem haul with tractors, and each had a capacity of 10 tons. CHEAP WAY OF INCREASING LINE CAPACITY To provide for growth in load the New York & Queens Elec- tric Light & Power Company, Long Island City, N. Y., was con- fronted, not long ago, writes H. C. Dean, General Superintendent New York & Queens Electric Light & Power Company, with the problem of increasing the rating of its distribution circuits about 30 per cent. In some districts it was possible to postpone the installation of additional copper in the feeders and obtain the in- crease merely by replacing 100-amp. regulators in the substations with 150-amp. or 200-amp. regulators. In the case of the Long Island City district, however, the current-carrying capacity of both feeders and regulators had been reached, and all regulators were of the maximum size (200 amp.) which the company con- siders it desirable to use. Choice of Systems. Three methods of solving the problem were open: (1) To install additional two-phase feeders (2300 volts, four- wire; (2) to install high-tension feeders and relieve the 2300-volt feeders of the larger consumers; (3) to change the 2300-volt, two-phase system to 2300/4000-Y volts, three-phase. The chief question at first was whether or not it would be as cheap to change from two-phase to three-phase as to leave the two-phase system and transfer the larger consumers to lines oper- ating at transmission voltage. A number of consumers are so supplied at the present time, and the company is looking forward to increasing such services to a large extent from now on. With the existing geographical layout of the lines and large consum- ers, the arguments were two to one in favor of changing the two- THE SYSTEM 121 phase distribution system. However, this was due to local con- ditions, and it is possible that for other companies the advantages would be materially different, either greater or less. Careful estimates showed that the third alternative would provide the necessary rating for less than half the expenditure required by the other methods, owing chiefly to the high cost of copper. It had the additional advantage that any future feeders would have 50 per cent greater capacity as three-phase feeders than as two-phase feeders, while the per cent line loss and volt- age drop would be only half as great. To determine the relative advantages of three-phase over two-phase, it was therefore only necessary to determine the valuation of the existing distribution system (less the poles) and to balance 50 per cent of this cost against the cost necessary to change to three-phase. In the Long Island City district the power load is about four times as large as the lighting load, consequently considerable work had to be done in making changes in the transformer banks. Although new consumers are provided with three-phase service, it was decided to continue two-phase, 230-volt service to existing 222 VOLTS 222 VOLTS g:, RATIO ^AA^AAAA/^ K/WVvAAA f 4O00 VOLTS K): I RATIO w> > <- s TRANSFORMERS *= < > c> K Fig. 36 — Method of Securing Converting from Two to Three-Phase WITH Standard Transformer consumers. This made it necessary to replace one transformer of each power bank with two of half the rating having 10 per cent taps. The connections and the voltages obtained are shown in the accompanying diagram. There are no theoretical disad- vantages in this method, as far as Mr. Dean can see, and it has given entire satisfaction for many months. Method of Making Change-Over. To facilitate the work on the day when each feeder had to be changed from two-phase to three-phase (which in every case was Sunday), the replacement of one transformer in each power bank with two of half capacity 122 CUTTING CENTRAL STATION COSTS was made in advance, the two smaller transformers being con- nected in multiple temporarily. The testing of all underground 2300-volt services, the replacement of certain cable not safe enough for operation at 4000 volts, and the installation of pot- heads on all cable ends, constituted the only other preliminary work on the feeders themselves. In the substation it was necessary to install a spare panel com- plete with equipment and three regulators for a three-phase TWO PHASE THREE PHASE -A AM/yv IB BUS m rA AUXILIARY ■ n BUS _ - • OIL CIRCUI T BREAKERS - - - -> CURRENT TRANSFORMERS FOR AMMETERS AND REIAYS ^m oi5oo| p oop POTENTIAt REGULATORS CURRENT TRANSFORMERS FOR LINE DROP COMPENSATOR ^ : POTENTIAL TRANS FOR INDICATING AND_. "CONTACT- MAKING VOLTMETERS <:<:<: 273 -• PLUG SWITCHES <-- TRANSFER BUS — PLUe SWITCHES Fig. 37 — Method of Arranging for Change-Over from T\vo-Phase to Three-Phase feeder and to provide for maintaining one of the 2300-volt buses at three phase. This spare panel and equipment was used for the first feeder changed over to three-phase, which thus released a two-phase panel and the corresponding equipment. The panel in turn was built over to provide for the second three-phase feeder, etc. On the day of actual change over of a feeder it was only neces- sary to change the connections of certain transformers and to transfer the feeder connections from the two-phase bus to the three-phase bus. Any power consumer who had to have service Sunday morning was permitted to use it until noon, by which time the fuse plugs of all power transformers were disconnected. The feeder was then switched from the two-phase bus to the THE SYSTEM 123 three-phase bus and the power consumers were given service in the order of their needs. The change did not require rearrange- ment of the overhead circuits. Economic Advantages. The change from two-phase to three-phase distribution in Long Island City district has resulted in a very decided economy, since it has made unnecessary the in- stallation of additional two-phase feeders, the expense of which W'Ould have been five times the cost of making the feeder changes to obtain three phase. Furthermore, it has decreased the line losses by approximately 200 kw., which alone would pay interest charges on the cost of making the change. In addition, it has improved the voltage regulation 100 per cent, which means that better service is given and that loads at great distances from the substation can be more economically handled than heretofore, thereby delaying the day when additional substations may be re- quired. RAISING THE VOLTAGE TO INCREASE LINE RATING As a matter of economy and to conserve the use of material the Louisville Gas & Electric Company has reconstructed the distri- bution lines throughout the city, changing the voltage from 2300 to 4000 volts by connecting the transformers in "Y." This ar- rangement greatly increases the line rating with very small in- vestment. A similar plan is being worked out for the heavy pow'Cr lines, the voltage of which will be raised from 6600 to 13,200. The latter change will release considerable transformer equipment since the largest turbine in the generating plant is wound for 13,200 volts. ECONOMY PROBLEMS IN NORTHWEST In order to care for an increase of power load at minimum ex- pense the Puget Sound Traction, Light & Power Company, Seattle, Wash., is taking advantage of the diversity of load be- tween power customers on its 2200-volt lines. Several customers, formerly served by separate transformer banks, are now supplied from one set of transformers with a combined rating of 200 to 300 kw. Larger transformers with the same combined rating for- 124 CUTTING CENTRAL STATION COSTS merly required now serve an increased load. In the case of some large customers, service is given directly from the 13,800- volt feeders. Rather extensive changes in the transmission system have re- sulted from the removal of lines which were not absolutely necessary, the equipment being used for new lines needed to serve industries essential to the war program. On the whole, about 20 miles (32 km.) of 55,000-volt line have been taken down and about 15 miles (21 km.) of new line have been erected with only a small amount of new material. At the same time the rating of the lines has been greatly increased. It should be noted, also, that this company has found outdoor substations built upon four wooden poles the least expensive. ECONOMICS OF POLE TIMBER Thrift and economy have become national watchwords, but we seem to have overlooked the ever-present decay of poles at the ground line and annually renew millions of poles still sound and serviceable above the ground, according to Ernest F. Hartman, President, Carbolineum Wood Preserving Company, New York. It is estimated that approximately 40,000,000 poles are in use to-day. Their value in 800,000 miles of lines has been fixed at $400,000,000. As a general average the life of poles has been placed at ten years, making annual renewals cost in the neighbor- hood of $40,000,000. On the basis of five poles per miles per annum for renewals, the drain on our forests will best explain the increasing cost of pole timber. While the treatment of poles before they are set is always to be recommended, this will not check the increasing consumption until a greater percentage are treated. At present only 25 per cent receive some kind of pre- servative treatment. Much can be accomplished in the way of more immediate saving by arresting the decay on poles already in service as hereinafter described. Such treatments will be a di- rect economy, as they save in the cost of poles as well as in the expense of resetting. It may also be taken into consideration that costs for line timber for some time after the war will remain at a very advanced level. About eight years ago Mr. Hartman made his first experiments on arresting the decay of standing chestnut poles. An examina- THE SYSTEM 125 tion just made shows that these poles, whose ground-line circum- ference was greatly reduced in preparing them for treatment, are still perfectly sound. After making a thorough search of all the literature on pole preservation for data on arresting decay, the desirability of gathering reliable information based on practical experience was realized. Accordingly the methods described rej)- resent a correlation of the available experience. It is the object of this discussion to encourage extension of such forms of pro- longing the life of poles to the millions actually in use. Treatment of Poles. The decay of timber can be prevented, retarded and, what is more important, arrested. If the poles are sound at the ground line, no great difficulty will be experienced. In this case it is only a matter of opening up the ground around the poles to a depth of at least 2 ft. (0.6 m.), allowing the poles to dry out and, after cleaning the area to be treated, applying three hot brush coats or sprayings of preservative,^ allowing just enough time between coats for the preservative to be absorbed by the wood. Treatment should extend 2 ft. (0.6 m.) above the ground line where the base of the pole is surrounded and shaded by vegetation. After filling in again one may rest assured that from five to eight years have been added to the life of the pole. If decay has set in, then it becomes a question of the extent to which the pole has been weakened at the ground line. Varying with the extent of the decay one of the following forms of pro- cedure will be found applicable : When only the sapwood shows decay, open up the ground around poles to a depth of from 2 ft. to 3 ft. (0.6 m. to 0.9 m.), shave away all the decay and allow the poles to dry out. Scrape surface checks clean with a chisel or other sharp instrument. Brush the shaved surface with a flexible wire brush, after which apply three heavy brush coats or a spraying of heated preserva- tive to the part at least 2 ft. (0.6 m.) above and 2 ft. below the ground line, allowing sufficient time between coats for the ab- sorption of the preservative. If the decay has gone beyond the sapwood and safety limits are not affected, it is recommended that the shaving away of the decay be followed with a heat treatment. Go over the shaved or scraped area with a plumber's torch and thus make certain that 1 Where specific directions are oriven for the application of preservative these apply to the use of "Protexol" (formerly "Avenarius Carbolineum") . 126 CUTTING CENTRAL STATION COSTS all wood-destroying organisms have been killed. A wire brush should be used to remove any charred wood. Then proceed with the application of preservative as before directed. Fill in with small stone (this will add a year or two to the life of the poles) or fresh ground, not sand. The old ground has in it the germs of decay and should not be used if the full benefits of the treatment are desired. Where poles show considerable checks at the ground line spray applications are preferable to the brush. An added life of five years can easily be secured. JOINT USAGE OF POLES Two or more lines of poles erected on the same side of the street or highway are not only unsightly but represent an eco- nomic loss and a waste of timber. Where the wires on such con- flicting lines are carried at or near the same level a serious elec- trical hazard to persons or property is liable to be created owing to the proximity of the wires of different classes and the liability of contact between them or the possibility of employees working on one class of wires coming in contact with another. The most practical way of eliminating the losses and hazards referred to in connection with lines located on the same side of the street appears to be a properly constructed joint-use line hav- ing a well-defined space for the wires and fixtures of each occu- pant, writes T. N. Bradshaw, chairman of committee which drafted Connecticut Rules on Joint Usage. These spaces should be separated from one another by an ample vertical clearance space. They should also be provided with a suitable climbing space so that employees of the various companies using the poles can ascend and descend them without coming in contact with the wires through which they may have to pass. A wide experience covering a number of years with lines con- structed as outlined above seems to indicate that' the clearance space should be not less than 40 in. (102 cm.) vertically between signal wires and attachments and electric light or trolley-feed wires and attachments. Experience also shows that a climbing space of not less than 30 in. (76 cm.) wide on either the back or field side of the pole is necessary in order to provide for climbing and for the raising or lowering of transformers. It is, of course, preferable to provide a greater vertical separation than 40 in. THE SYSTEM 127 ^5 H U H O o p w H o c >■ Q < M I-) O !< O CC U OS o M o G < '^ o M m of o PM o cc f? o 02 o PlH M H < cc CO d 128 CUTTING CENTRAL STATION COSTS between signal wires and wires carrying high voltages, and many companies endeavor to have this space not less than 6 ft. (183 cm.) particularly with new lines, using the minimum clearance of 40 in. only on old lines that are made joint after the line has been in service for some length of time. The street side of the poles should always be reserved for the vertical runs of the electric light or power wires, and the field side for the vertical runs of signal wires. Owing to the fact that there is no known protective device that can be placed on a signal circuit that will afford adequate protection against the potentials carried on high-tension circuits, it is not considered advisable to place telephone, fire-alarm or other signal circuits on the same poles with such circuits. High-tension lines should wherever practicable be constructed on rights-of-way remote from those occupied by the signal lines. (By high-tension circuits are meant the following: Constant-potential, alternating-current, neither side grounded, exceeding 5000 volts; constant-potential, alternating-current, one side or neutral grounded, exceeding 2900 volts to ground; constant-current, series-metallic, line cur- rent exceeding 7.5 amp., and constant-potential direct-current circuits including feeders and trolley-contact wires, one side grounded, exceeding 750 volts to ground.) Pole lines located on the opposite sides of a street or highway are not considered as conflicting, but the same precautions should be observed, when erecting separate lines of poles, regarding the relative levels of the wires of different classes. That is, electric light or power wires should be carried on a taller pole line and the signal wires carried on a shorter pole line. This will enable elec- tric light service wires crossing the streets to be carried over the telephone wires, and telephone wires from the opposite side of the street to be carried under the electric light wires. This prac- tice prevents the interlacing of the service wires, which is liable to be a very serious problem in streets which are congested to any considerable degree. In order to bring about the conditions outlined in the fore- going it is necessary to have some form of inter-company agree- ment covering not only specifications and methods of construc- tion and the reservation of space requirements but also a fair division of the construction and maintenance costs. In Connecti- cut the matter is helped along by fair-minded legislation, and the Public Utilities Commission of Connecticut has promulgated THE SYSTEM 129 in its Order ^'D" docket/ No. 1447, a set of rules and specifica- tions under which most of the wire-using companies of the state have been operating for some time with very satisfactory results. Since most of the lines in Connecticut have been placed on a joint-use basis and the construction standardized there has been a marked decrease in the number of fatal accidents to the em- plo3'ees. This is undoubtedly due to the fact that employees working on signal circuits no longer have to climb through elec- tric light wires in order to get at their own work, and the electric light wires are generally placed so far above the signal wires that electric light employees are not apt to come into contact with grounded lines of another class in working on high-voltage wires. There is another feature which appears to make joint use pref- erable, particularly in cities and towns where there is consider- able local distribution ; that is, that the city or town is more com- pletely covered by the pole lines of the two companies, and many companies have reasoned that it is better to own one-half of all the poles in a locality rather than to own all of one-half the poles. In order to insure the success of any joint-line arrangement, particularly where electric light and signal lines are to occupy the same poles, the broadest possible cooperation must be in- dulged in between the various occupants for eliminating induc- tive interference. Electric light lines should always be kept free from grounds that might upset the electrostatic balance to ground, also long single-phase taps from three-phase circuits should be avoided wherever practicable. The voltage wave de- veloped by the generators should be as free as possible from noise- producing harmonics, and consideration should be given this fact before the generating machinery is purchased from the manu- facturer. Deviation from the pure sine wave should not be allowed to exceed the limit set by the American Institute of Elec- trical Engineers. These precautions are quite necessary in con- nection with electric light or power circuits, because it is not always possible to transpose telephone lines, for instance, so as to eliminate all inductive interference. In many instances it has been found necessary to place transpositions in the electric light or power circuits to coordinate with those in the telephone cir- cuits. 1 Can be obtained by addressinof secretary of commission, Henry F. Bill- ings, whose address is Hartford, Conn. 130 CUTTING CENTRAL STATION COSTS In Connecticut alone there are approximately 1700 miles (2700 km.) of pole lines used jointly by electric light and telephone or other signal lines. Practically all of this joint line mileage is standard as regards location of the wires and vertical or lateral separation, so that it is fair to say that the joint-use line is, under proper regulation, a success, simplifies the distribution problem and works toward safety. While it is sometimes more expensive to erect a joint line, the cost to each occupant is usually less than a separate line or poles would be. The maintenance costs are also less because of this division of the charges. The lines appear to stand up better under the influence of severe storms because of the fact that such joint-use networks are usually much better guyed or braced than a single line would be. Moreover, such lines receive more atten- tion from the engineers in order to make them satisfactory to all parties concerned. TRANSFORMER INSPECTION AN ECONOMIC MEASURE Thorough inspection of all distribution transformers returned from the lines should be made before they are again issued for service, first to lessen the chance of failure after replacement on the lines, and second to minimize the labor required in making the installation. Chances of failure are decreased if transformers are issued thoroughly clean and dry and with leads and bushings intact. Moreover, it is evident that minor repairs and adjust- ments can be made better and cheaper in the shop than by the in- stallation crew in the field. Bushings Need Close Attention. Bushings should always be carefully examined, as they are a frequent cause of failure. This is particularly true of the higher voltage classes (11 kv. to 22 kv.) owing to their sizes and greater liability to breakage. A break is not always evident from a casual examination, and each bushing should be shaken to disclose any looseness. A broken or loose bushing, especially a primary bushing, should always be repaired before the transformer is again utilized, since it is almost certain to break down in wet weather and may, under certain conditions, cause a burn-out of the transformer 'windings. As most bushings are broken in handling transformers after shipping crates have been removed, means should be provided THE SYSTEM 131 for protecting them. This is especially necessary with the comer bushings of the flaring petticoat type used in transformers de- signed for moderately high distribution voltages since the insula- tors project beyond the re-entrant corners in the case. Some companies provide wooden angles which are bolted to the hanger lugs and encircle the bushings, thus eliminating breakage when the transformer swings against an obstruction. Although more liable to breakage, double petticoat bushings with long leakage surfaces and deep recesses seem to give better service than the straight or corrugated types. The recess seldom becomes entirely filled with oil and dust, regardless of how much the lead may siphon oil. Furthermore, leakage will not occur across the clean surface between the two parts of the shell. On the other hand, the cylindrical types, whether plain or corru- gated, usually become coated with dust whenever there is any oil leakage, and breakdown often results. In renewing bushings in any line of transformers advantage should be taken of the most recent designs that may be accom- modated in the outlet holes. Thus it will be found that the early white cylindrical types may in some instances be replaced with corrugated brown glazed bushings, which, having a longer leak- age surface, are less liable to break down. It is important that bushings which are suitable for the service be chosen. Substitutions should not be made unless the new type is superior to the old. A full supply of spare bushings should be carried in stock so that makeshifts will be unnecessary. A blue- print schedule showing the catalog numbers of primary and sec- ondary bushings required for each tank number should be pre- pared with the assistance of the manufacturers for each line of transformers handled. This will be found of service both in ex- pediting purchases and in selecting repair parts from store-room stock. When installing new bushings a grade of sealing compound such as is specially recommended by the manufacturers for this purpose should be used. All of the old compound should be re- moved before the new bushing is placed. If the bushing is of the type set in with babbitt (those inserted from the outside are usually set in with babbitt, paper lock washers or some similar device), this metal also should be completely removed. In chip- ping out old bushings and compound provision must be made 132 CUTTING CENTRAL STATION COSTS for catching the scraps to prevent their falling into the coils or bottom of the case. Bushings of the curved styles are best made up complete with leads before insertion in the transformers. The more simple styles, which are easily filled with compound, may be filled in place. Heating Compound to Right Temperature. Care must be taken to heat the compound to the proper temperature before pouring; otherwise cracks will result. The entire corner of the case in which the bushing is placed should be heated so that the compound will not be chilled on striking the metal. To chill the compound will often result in a leak between it and the case. Much of the oil leakage which occurs around leads and bushings is not caused entirely by siphon action along or through the lead, but may be due to cracks between the bushing and the sealing cement or between the latter and the case. This leakage will not occur unless oil is slopped onto the compound, but it is prac- tically impossible to avoid this in handling a filled transformer. To avoid leaks of this character, not only should hot compound be used, but the surface of the compound above the bushings should always slope in toward the center of the case. This can be effected by tilting the transformer while the compound is being poured as well as while it is hardening. "Where the compound must be built up a temporary paper dam may be installed, and after the cement has set it can be removed. This scheme also makes it possible to raise the level of the cement above the top of the bushing so that the bushing and recess may be filled in one operation. Bushings should be kept clean. It is a good plan to incor- porate in all directions covering the installation of transformers a note to wipe bushings carefully after the transformer is in place. Most of the oil and dust which, if left on a bushing, are so likely to cause breakdown are accumulated during transportation from the store room to the job. If the bushings are cleaned after the transformer is hung, this cause of trouble is largely avoided. When transformer tanks are being painted care must be taken not to get paint on the bushings, as the rough paint surface will tend to gather dust. Bushings of the larger types should be wrapped with cloth or paper while cases are being painted. How Trouble with Leads May Be Prevented. Next to bush- ings, leads require most frequent attention. They are often THE SYSTEM 133 broken in handling or are cut short when transformers are re- moved. In addition, they deteriorate because of the siphoning of oil. Secondary leads of the types of transformers under discus- sion are invariably rubber-covered. Primary leads are usually rubber-covered, although some manufacturers have recently used varnished cambric insulation for voltages of 11 kv. and up. Each material has its advantages. Rubber withstands weather and moisture well, but it is deteriorated rapidly by oil. This weakness is its most serious defect as oil is often siphoned over the leads. Varnished cambric, on the other hand, while bene- fited by oil, does not withstand weather well when protected only by a braid covering. It is easily dried out by hot weather and is liable to absorb moisture in wet weather. These remarks ap- ply, of course, only to the leads outside of the case ; those inside are always insulated with varnished cambric. In arranging for shop repairs to transformer leads it is first necessary to prepare a schedule of cables to be used in making renewals, in order to secure uniformity in purchases and repairs. This is preferable to attempting to replace the old lead with one precisely similar in size, insulation and stranding to that installed at the factory, since in the past manufacturers have differed con- siderably as to these details in transformers having identical rat- ings. To follow these deviations would require an unnecessarily elaborate stock of cable. A schedule which has proved satisfac- tory in practice is given herewith for two classes of transformers, for an 11,000-volt and a 2300-volt line. The cables selected, es- pecially those used for primary leads, have not been chosen ex- clusively on a basis of their usefulness as transformer leads, but also with a view to their use in the wiring of substations and similar work, in order to avoid the carrying of overlapping stocks. All cables are specified as single-braid, rubber-covered. However, if any are to be used extensively in outdoor work, as for instance in wiring between cut-outs and transformers, they may be specified as single-braid and tape. The rubber insula- tion is 30 per cent Para for the 11-kv. leads and N. E. C. for the others. It is evident that cable much smaller than No. 6 might be used for the smaller sizes of 11-kv. transformers. However, the ex- pensive part of cable is the insulation, therefore little saving per foot can be effected by ordering a smaller size. Since this size is 134 CUTTING CENTRAL STATION COSTS used extensively in transformer installation wiring, short pieces are usually available for leads which might otherwise be wasted. The greatest difficulty in installing leads is to prevent the si- phoning of the oil. If this happens, the oil will rapidly deterio- rate the rubber of the leads and in addition will gather dirt on leads and bushings and thus increase the danger of breakdown. VARNISHED CAMBRIC INSlJIJiTION F/UIN5 HOLE ' Fill Infer sf ices be-fween Strands with Solder fo this Point '•—Sfop Endwifh Clolh while filling/ ■ RUBBER INSULATION ■STRANDED CONDUCTOR READY rOR SBIVia CM»ny H». Me TcsM by MouMn. nwsronn RSI MNii ml072 IMt ^.. Cydo. vdts rn Vo«s II Con t«ss W>Hs. . ln«ii(ilioii Volts bc.Ciif.Ai.pj. Riti«_ — R«|(«r«l»mlletrtby . Repairs ni4< and IKW pifte hsbM— Returio: ur^ , ■ ^ , —CHANOE tNST.NOeOOADDL. INSri^'PeUY CHANGE NQ ST0NQ30 CHANGE NO. 3 TO NO 30 'DEAD END SEC. S 3310 "^^M .REM. POLE ^HURCHILL ST. REMihaep.M^^^'^'^ Fig. 43 — Typical Method of Indicating Work on Job Order ents engaged in the work. Next, it reduces the amount of ma- terial which has to be carried in stock by reducing the number of kinds of units needed. Third, it permits of accurately deter- mining in advance the correct amount of material needed on each job, since the material for each standard is definitely known and the material for a job will be equal to the sum of the material for the standards in connection with the job. In addition, it increases the efficiency of the gang, owing to the fact that the repeated performance of a job in a definite way increases the speed with which it is done. Again, it establishes uniform con- struction throughout the system. Sixth, it permits a comparison of the relative value of the gangs, as each gang does the same units of work in the same manner. And last, but not least, it reduces the cost of doing the work. The establishment of standards for overhead construction is THE SYSTEM 151 not so simple as iii most other work, liowever. No two jobs are alike and, while the elements of a job may be similar, the eon- ditions under which it will be done are different in each case. However, if overhead line work is to be made uniform, simple, neat in appearance and easy to designate, there must be stand- ards. The method of establishing such standards for the Com- monw^ealth Edison Company of Chicago are given in the follow- ing paragraphs. In this program of standardization, which extended over a period of two years, several requirements were considered. They were safety, simplicity, neatness in appearance, uniformity, practicability, fitness for a progressive construction program, and cost. How Cable Pole Construction Was Standardized. In order to give a concrete illustration of the manner in which some of these requirements have been met, the steps followed in standard- SERVICEARM Fio. 44 — Standard Cable-Pot-e Constiiuction Adopted izing a cable pole will be explained. When the standardization of cable poles was considered it was found that there were several types of construction in existence. This condition existed bo- cause men in charge of work in various districts had followed their own ideas and worked independently. The best type was selected, and the question of safety was first considered. Tliis pole contained six alley arms and three buck-arms and was de- signed to carry twelve potheads. It was found that the safety of the pole could be improved by adding another arm, on wiiich the lineman could stand while inspecting lightning arresters. 152 CUTTING CENTRAL STATION COSTS This further loaded the already overburdened and unsightly pole. While the question of safety had thus been taken care of, sim- plicity of construction and neatness in appearance had been neglected. In order to attain this it was necessary to reduce the number of arms on the pole. It was found that the number of cases in which it was necessary to install twelve potheads on a cable pole were few. Therefore it was decided to design the cable pole for eight potheads, taking care of the cases in which twelve potheads were needed by setting another cable pole. This permitted the reduction of the number of buck-arms by one. The standing arm, which was originally installed for safety in inspecting lightning arresters, was then eliminated by installing the non-inspecting type of lightning arresters. Further consideration resulted in the elimination of services from the cable pole, and a standard was finally adopted having only three buck-arms and four line-arms as against the old type, which had four buck-arms and seven line-arms. The new standard (Fig. 44) is safer, simpler, neater in appearance, more practicable and costs less than any construction which was formerly used. A good illustration of progressive construction is given by the present type of standards for transformer installations. An in- FiG. 45— Typical Construction for Small Transformer Installations vestigation of the different types of construction brought out the fact that, as was found with the cable poles, there were many methods of installing transformers. It was also found that as the load on a transformer increases, and it is necessary to increase its size and therefore increase the strength of the equipment for THE SYSTEM 153 holding the transformer, it would be practically necessary in most cases to dismantle the previous construction and rebuild the transformer pole. Safety and appearance were already- fairly well taken into consideration, so that the main question was one of progressive construction. In the plan which was finally adopted the transformers are divided into groups with a type of installation for each group. The installations are so planned that when it is necessary to increase the size of a transformer of one group to the next larger PRIMARY MAIN ■ STANDARD 4-'^IN ALLEYAFtM PRIMARY PHASE TANDARD 6-PIN CROSS ARM SECONDARY MAIN 6 T7?ANSP0RM£R ARM c- HEEL ARM Fig. 46 — Ample Space is Provided for Large Transformer by Bracing Used, While Extra Strength is Afforded by Double Buck-Arm Holding Transformer it is merely necessary to add another arm without disturbing the existing equipment other than the transformer itself. Incident- ally, simplicity and neatness in appearance were attained by pro- viding heavier arms to support the transformers rather than b}^ doubling the smaller sizes of arms (see Figs. 45 and 46). A change from the construction shown in Fig. 45 to that in Fig. 46 can be made by merely adding a short buck-arm for additional strength without any change in Aviring. Once having established a standard, there are two things to be accomplished in order to put this standard into effect : First, to familiarize the man on the job with the construction standard ; second, to devise a scheme for specifying the standard on the job print. In order to keep the man on the job in touch witli standard construction, each gang foreman is supplied with a book of standards known as the ''Overhead Construction Specifi- cations." This book is pocket-size and contains a description of 154 CUTTING CENTRAL STATION COSTS the methods of construction and prints of all the standards com- monly used, together with a list of material for each type of con- struction. The foreman is thus furnished with authoritative in- formation on whatever work he has in hand. On account of the large number of standards of overhead con- struction, it was evident that some system of symbols must be 4-PIN ALLEY ARM 6-PIN ALLEY ARM Fig. 47 — Pole-Top Construction Classified by Position of Ceoss-Abms ON Pole adopted in order that the standards might be classified and to permit ease of reference and specification on the job print. For this purpose the standards are divided into groups according to types — for example, cable poles in one group, transformer poles in another, line poles in another, etc. To each group is given a series of numbers sufficient to take care of the present standards THE SYSTEM 155 and to allow for future standards that may be established. These symbols or numbers for designating the different types of stand- ard construction permit ready reference to the various groups and allow the use of simple specifications on the prints and jol) sheets. The foreman and men soon become familiar with the symbols and refer to the types of construction by symbol numbers instead of by description. In attempting to establish standards for the overhead work, it was found that they naturally divide themselves into two groups — one line poles, the other special poles. The number of special poles is limited, and it was a simple matter to assign symbol numbers to them ; but when it came to the question of assigning symbol numbers to line poles it was found that there were so many possible combinations of arms on a pole that the making of a sketch and assigning symbols to each combination was out of the question. It was therefore necessary to establish some scheme that would permit the definite designation of the arming of a line pole without the necessity of assigning to each group of arms a separate sketch and symbol. Study on a scheme of this kind resulted in the application of a decimal system (Fig. 47) for designating the arming of line poles. For instance, referring to the group of small figures in this illustration, Fig. 1 is a four-pin alley arm on the top line gain. When placed on the second line gain it is called Fig. 10 ; on the first buck gain, Fig. 100, and on the second buck gain, Fig. 1000. The arm doubled is designated by the next even number. In other words, the number designates the arm, and the units, tens, hundreds or thousands in a figure designate the position of the arm on the pole. For example. Fig. 30 represents a six-pin alley arm on the second line gain — the figure 3 identify- ing it as a six-pin alley arm, and its being in the tenth position identifying its location on the second line gain. The s])eeifying of the arming of a line pole is thus reduced to a symbol consisting of no more than four digits, and any combina- tion of four arms, either single or double, on any of the four positions can be specified by means of the decimal system shown. To illustrate further: Fig. 632 designates the arming of an ordinary line pole from which a service is taken and specifies that a double four-pin alley arm is installed on the top line gain, a 156 CUTTING CENTRAL STATION COSTS single six-pin alley arm on the second line gain and a double six- pin buck-arm on the first buck gain. The simplicity of the desig- nating of the arming of line poles should be evident. WOODEN TOWER FOR A LONG-SPAN CROSSING To supply Camp Pike with service promptly the Little Rock Railway & Electric Company had to erect a 13,000-volt transmis- sion line within a very short period. Since the camp was on the opposite side of the Arkansas River from the company 's generat- ing station, a 2000-ft. (606-m.) span had to be provided to cross the river. One bank of the river was about 160 ft. (48.7 m.) higher than the other, so that a relatively tall tower was required on the lower side. Not being able to secure steel towers on short notice, the company erected a wooden one. The tower was constructed of four 75-ft. (23-m.) red-cedar poles securely embedded in concrete and cross-braced with 6-in. (15.2-cm.) diagonals. Cross-arms, 4 in. by 6 in. (10 cm. by 15.2 cm.), were used. The total cost of the tower, which, furthermore, was com- pleted in the required time, was less than one-tenth that of the steel tower of the same strength. Of course, the wooden struc- ture will not have so long a life as a steel one would have had, but it is adequate for the purpose, as service will have to be sup- plied only temporarily. BRACING LINE TOWER By means of attaching a latticed structure to an ordinary straight-away line tower and then guying it at right angles to the line a company in New England was able to use a standard tower where an angle tower would ordinarily have been required. By so doing it avoided buying a special tower which would have been more expensive than the structure used. A branch line is attached to the tower at right angles to the through line at this point. This arrangement has proved per- fectly satisfactory from a structural point of view, and in these daj^s when economy has become compulsory it has much to recommend it. THE SYSTEM 157 STEEL CONDUCTORS FOR SERIES CIRCUITS Although the use of steel conductors in transmission and dis- tribution circuits has advanced considerably, writes L. M. Klauber, superintendent Electric Department San Diego Con- solidated Gas & Electric Company, as a result of recent material markets, many companies still hesitate to use the cheaper metal because early experiments in some cases proved failures. Such failures have been both mechanical and electrical. Mechanical failures have occurred owing to rapid corrosion of the conductor or to annealing following short circuits. Most of these cases, however, have been found upon investigation to have involved the use of solid conductors of comparatively small size, such as No. 6 or No. 8 B.W.G., attempts having been made to use con- ductors similar in mechanical form to the copper superseded. Extra-galvanized stranded steel, on the other hand, has long been extensively used for guys, and its life as a conductor ma}^ there- fore be closely estimated by any central station, the estimate being based on the performance of guys in the same regions. Electrical failures have been due to insufficient data on the electrical characteristics of steel conductors, and particularly to lack of consideration of the skin effect in solid conductors, which results in excessive drop at higher current densities. But exten- sive data on this subject have recently appeared, especially cover- ing the stranded steel largely used in guys, so that the principal uncertainty which now remains has to do with the characteris- tics of the load, both present and prospective. Obviously, sav- ings through the use of steel result primarily from the fact that in certain classes of lines copper of greater cross-section than is electrically necessary must be used for mechanical reasons. For this reason, an economical steel substitute will have less capacity for increased load than the copper replaced. It is therefore essential in designing steel lines that regulation and losses be closely calculated and that suitable allowances be made for future load increases. One case in which most of the factors and results may be closely calculated in advance has to do with the use of steel con- ductors in series street-lighting circuits. In this case current and hours of use are fixed so that losses may be predetermined exactly. Since increased load involves increased pressure per 158 CUTTING CENTRAL STATION COSTS circuit or increase in number of circuits, there is not the possi- bility of having to replace steel with copper upon acquisition of unexpected new business. Furthermore, there is no possibility of deterioration of the line by annealing during short circuits. If stranded steel guy cable is used, the life may be gaged from previous performances. Formula for Choice of Conductor Material. It is obvious that the economical choice between steel and copper will depend on a number of factors which are different for each individual case. Of fundamental importance are the costs of the two ma- terials, rates of interest and depreciation and the cost of energy. In general, it may be said that steel will be the cheaper when the annual fixed charges on a copper line are greater than the fixed charges on the steel line plus the increased energy losses by reason of the use of steel plus the fixed charges on the additional constant-current substation apparatus required because of the greater losses in the steel as compared with copper. Stating this in the form of an equation: FcCc — FsCs — L{HW + FeCe) =X. It will be more economical to use steel when X is positive ; when X is negative copper is preferable. In the preceding equation, Fc, Fs and Fe represent respectively the rates of interest plus depreciation on copper lines, steel lines and substation equipment. Cc and Cs represent the first cost of unit lengths of copper and steel lines. This cost must be the cost in place, including overhead expense, since when lines must be removed the total cost in place must be retired from service. Ce represents the first cost of series lighting transformers per kilo- watt. L equals the excess loss in kilowatts in a unit length of steel over copper. This quantity evidently depends on the current in the series circuit and the relative resistances of the two conduc- tors at this particular current density, it being remembered that the alternating current resistance of the steel varies with the current density. H represents the annual hours burning in the street-lighting system under consideration. TV is the cost of energy per kilowatt-hour delivered at the substation buses ; this item should, however, include only those elements of production cost which vary with output (i.e., fuel cost in steam plants). Were the relative prices of steel and copper to remain in con- THE SYSTEM 159 stant ratio with markets fluctuating proportionately, either the one metal or the other would be invariably preferred for certain circuits. This, however, has not been the case, especially under recent abnormal conditions, as shown by Fig. 48, which gives the relative costs of steel and copper deduced from the purchasing department records of one central station for the last eight years. It may be seen that the cost of copper wire has varied from about twice to nearly five times the value of steel wire. Under such changing conditions it is logical that sometimes one and some- times the other metal is more economical. Application of Formula to a Particular Case. In order to illustrate the application of the above formula, two cases are assumed, one comparing bare copper with bare steel, the other double-braid weatherproof copper with weatherproof steel. The prices assumed should not be considered as indicative of present costs, since they are rather those which applied some months ago : In giving values to Fc, Fs and Fc interest is taken at 6 per cent. Bare copper is assumed to have a life of thirty years and a junk value of 40 per cent. (In each case the junk value represents the sale price as junk less cost of removal.) Weatherproof copper is presumed to have a twenty-year life and a 30 per cent junk value, since the serviceable life of an insulated conductor is in reality the life of the covering; for, regardless of the life of the metal, it must be removed when the covering becomes abraded. For 1910 1911 1912 1913 1914 1915 i9li5 1917 I9id Fic. 48 — Fluctuations in Ratio Between Copper and Steel Costs During Nine Years this service weatherproof steel may be assigned the same life as copper, although the junk value will be zero. Bare double-gal- vanized steel under normal conditions (away from salt fogs or corrosive fumes) is assumed to have a life of fifteen years and to be without net salvage value. Constant-current transformers are assigned a life of thirty years and a salvage value of 10 per cent. Basing depreciation calculations on the straight-line 160 CUTTING CENTRAL STATION COSTS method and adding interest at 6 per cent, the following conditions exist : Weatherproof Bare F^ 0.095 0.080 fI 0.110 .0.1267 F 0.090 0.090 e Practically all series lines are No. 6 copper, so only this size will be considered. The best steel substitute appears to be %-in. (0.63-cm.) extra-galvanized standard steel strand. Assuming copper (weatherproof or bare) at 34 cents per pound (75 cents per kilogram) at the storeroom, bare steel at 8 cents (17.6 cents) and weatherproof steel at 11 cents (24.2 cents), adding 4 cents per pound (8.8 cents per kilogram) as the cost ^ of stringing and 15 per cent overhead, and considering 1000 ft. (304.8 m.) as the unit of length throughout, with bare copper weighing 79.5 lb. per 1000 ft. (118 kg. per km.), double-braid weatherproof copper 100 lb. (149 kg. per km.), bare steel 125 lb. (185 kg. per km.) and weatherproof steel 155 lb. (230 kg. per km.), the following is true: Weatherproof Bare G^ . . , $43.70 $34.74 C"" 26.74 17.25 s (0 is assumed to be $12.50.) In the determination of L the resistance of copper is taken as 0.395 ohm. Within the comparatively small range of commercial alternating-current series circuits (4 amp. to IV2 amp.) there is little change in the resistance of M-in. (0.63-cm.) galvanized steel, the total increase at the higher density being about 3 per cent above the lower. This is less of a variation than that found between individual samples and may therefore be neglected. The 60-cycle alternating-current resistance of %-in. (0.63-cm.) extra-galvanized seven-strand standard steel at these densities has been found by various investigators to be from 1.62 ohms to 1.78 ohms per 1000 ft. (5.3 ohms, to 5.8 ohms, per km.). Taking 1.70 as an average, and assuming a 6.6-amp. series circuit, L = 0.0568, H may be taken as 4000 for all-night lighting cir- cuits, 2600 for moonlight and 2200 for midnight circuits. W 1 There is practically no difference in the cost of erecting copper and steel. THE SYSTEM 161 obviously differs for each individual case and is here taken at $0,005. Substituting the preceding values in the equation, the follow- ing values of X are obtained : 'to Circuit Weatherproof Bare All-ni(;lit 0.01 — 0.61 Moonlitrht 0.41 — 0.21 Midniglit 0.52 — 0.10 Thus in each assumed case it will be found more economical to use weatherproof steel rather than weatherproof copper, but bare copper (if line and ordinance conditions permit the use of un- covered conductors) is to be preferred to bare steel. Assuming the same constants but a 4-amp. circuit, L = 0.0209 ; therefore it will pay to use steel in every instance. Most Economical Size of Wire to Use. Of the various sizes of standard steel strand, %-in. (0.63 cm.) will usually be found preferable for series circuits. Smaller sizes lack strength and are not so readily obtainable as the sizes used for guys. Al- though largely used in multiple circuits where steel is employed, 5/16-in. (7.9-mm.) cable will generally be less economical than Vi in. in series circuits. This can be shown as follows : Consider 5/16-in. bare steel weighing 210 lb. per 1000 (312 kg. per km.) and double-braid weatherproof weighing 255 lb. (378 kg. per km.). By substituting the same unit prices and depreciation rates as were assumed in the case of %-in. cable, omitting fixed charges on substation equipment, as they are of minor impor- tance, and assuming that tlie alternating-current resistance of 5/16-in. (7.9-mm.) standard strand is 1.25 ohms per 1000 ft. (4.1 ohms per km.) at the current densities under consideration, the original equation reduces to : 1.486 — 0A5PnW = X for bare and 1.898 — OA^PHW = X for weatherproof. Thus for 6.6-amp. series circuits it will be more economical to use 5/16-in. (7.9-mm.) strand than ^/4-in. (0.63-cm.) cable only when the cost of energy per kilowatt-hour at the substation ex- ceeds the following : Weatherproof Bare All-niOSS Af?M JRON STRIPS Fig. 5G — Extra Cross-Arm on Pole-Top Extension Flat iron strips 3 in. by 0.5 in. (7.6 cm. by 1.3 cm.) were at- tached to the pole near the top and bent at right angles at a suit- able distance above the pole top. The extra -cross-arm providing for six insulators was attached to these iron strips by means of lag screws. This scheme gave additional height to the pole and eliminated the necessity of another pole line. It has given satis- factory^ service, writes Frank Huskinson, on a transmission line one mile in lenorth. INEXPENSIVE OVERHEAD LINE CROSSING AT RAILROAD Two three-phase transmission circuits of the Fort Smith (Ark.) Light & Traction Company have been strung across a railroad right-of-way on supports attached to an overhead bridge. THE SYSTEM 179 This type of construction was chosen in order to avoid the use of extra-high poles and to make a permanent job. The arrange- ment, as worked out, proved inexpensive. At each end of the main bridge span tubular steel trolley poles were attached to upright members of the steel bridge by means of three large U-bolts. These steel poles were also braced at the top by gu}^ wires and by an angle-iron framework which supported the trolley wire over the track. The fact that the high-tension circuits ran parallel to the track on one side of the railroad and at right angles to it on the other made different types of construction necessary at each support. On one side strain insulators and short ''pull-off" wires served to support the wires at this right-angle turn and to give ample clearance between the circuits and the steel bridge span. On the other side of the bridge seven strain insulators hung in a continuous string are supported between angle-iron mast arms attached to the trolley pole. The high-tension wires are then supported at the points between the strings of insulators. THE OUTDOOR SUBSTATION On account of the rapidity with which most of the materials covered by war contracts had to be delivered, industrial com- panies found that the building of isolated plants was out of the (luestion, not only because of the time necessary for erection, but because of the low rates and excellent service furnished by utility companies. As a result central-station companies had to make numerous extensions to their plants to take care of the demands imposed upon them by the war industries. The difficult}^ of ob- taining material on short-time delivery, the speed with which the installations had to be made, and the need of conserving funds, all made it imperative that all central-station equipment be util- ized to the best advantage. With this idea in mind, many cen- tral-station companies adopted the practice of providing outdoor substations for serving the various war industries which were de- pending upon them for power. The development of electrical apparatus and equipment has been such in recent years that it need no longer be operated indoors. The use of outdoor substations, therefore, according to E. B. Meyer, Assistant to Chief Eng^ineer, Public Service Electric 180 CUTTING CENTRAL STATION COSTS Company of New Jersey, was one of the means of hastening the end of the war in that it was no longer necessary to provide costly fireproof structures for the housing of electrical equipment. Outdoor installations can be made at a greatly reduced cost and the saving in both labor and material is therefore an item which should not be overlooked. For small outputs and comparatively low voltages the trans- formers are usually hung from a substantial pole directly un- derneath the transmission line itself, the switching equipment being mounted on cross-arms between the line and the trans- former, and the transmission line carried on top of the pole. Transformers of larger output or higher voltages are mounted on platforms, sometimes they are arranged on steel towers and at other times on wooden structures supported between two or more poles, while the switching equipment is usually carried immedi- ately above the transformer. For the largest outdoor substa- tions the transformers are mounted on guarded concrete plat- forms, while all of the switching equipment and transmission lines are carried on steel towers of strong construction. Substations of the portable type, with the apparatus mounted on wagons, floats or railway cars, are particularly adapted for breakdown auxiliary service, temporary peak loads, construction work or any of the other numerous war-time demands made upon the central-station companies. It was originally supposed that the outdoor station created a greater hazard to the public than one in which all the equipment is housed, but this fear is groundless since with the property in- closed by a substantial fence the danger to the public is elim- inated. With the outdoor substation there should always be less danger from fire, provided proper precautions are taken against the accumulation of inflammable material on the property. Requirements of an Outdoor Station. In the design of an outdoor substation it is desirable that the installation be as neat and compact as possible. Usually elaborate switching equipment is not necessary to provide immunity from interruption as in most cases interruptions are so infrequent that the cost of pro- viding duplicate and expensive equipment is not warranted. The outdoor installation, as well as all other forms of high-tension installations, should be so arranged as to make the operation as THE SYSTEM 181 simple as possible and at the same time provide ample protection to the operators and repair crews. In a number of outdoor substations steel structures are used for mounting the buses, disconnecting switches and other equip- ment. The difficult}' at this time of obtaining delivery on struc- tural steel and the advisability of conserving this material for shipbuilding and other important war needs has made it neces- sary to look about for some other type of construction. Heavy wood poles and timber construction may be used to good ad- vantage and at the same time reduce the cost considerably. Storage of Oil During Transformer Repair. In installations where large capacity oil and water-cooled transformers are used it is sometimes necessary to provide a tank for storing the oil from transformers under repair. Oil tanks are usually built of boiler plate, but as this class of material is one of those on the list which must be conserved for war purposes, it is necessary to pro- vide some other form of construction as a substitute. One large central-station company where a number of high-capacity oil and water-cooled transformers are used has experimented with a con- crete tank for oil storage. In the particular installation in ques- tion a concrete tank 13 ft. by 6 ft. by 6 ft (4 m. by 1.8 m. by 1.8 m.) was built adjacent to the outdoor installations and so arranged that the oil can be drained from the transformers directly into the tank. The tank is built with a mixture of one part cement, two parts sand and four parts broken stone and reinforced rods to make a structure of sufficient strength to with- stand the oil pressure. The interior of the tank is plastered with a waterproof compound, over which are applied several coatings of silicate of soda. An airtight cover is provided on the top of the tank and the necessary provisions are made to allow pump- ing the oil back into the transformers when repairs have been completed. It is not expected that the oil will have to remain in the concrete tank for any great length of time so that the leakage, if there is any, will be practically negligible. The mat- ter of providing proper housing for repairs and storage of oil may at first seem to be somewhat of a refinement ; it nevertheless is important in large installations if it is desired to keep the cost of repairs at a minimum and at the same time avoid delays in placing equipment back into service. In many instances lack of 182 CUTTING CENTRAL STATION COSTS attention to the matter of repair facilities has resulted in delays, with a consequent loss in revenue to the central-station company. It must not be inferred, however, that making repairs consti- tutes a serious difficulty, as with reliable apparatus and proper accessibility it is often easier to make repairs outdoors than indoors, where lack of room sometimes handicaps the repair men. Cooling Transformers. Adequate cooling may be provided for transformers by three different methods : (1) Cooling tower ; (2) spray pond; (3) deep-well pumping outfit. The objection to the spray pond is the amount of room required for this type of installation, as in order to obtain sufficient spraying surface an area 50 ft. by 50 ft. (15.2 m, by 15.2 m.) is required for even a moderate-sized installation. A cooling tower may be of two types, one commonly called the forced-draft cooling tower and the other the atmospheric cooling tower. What might appear to be an objection to both the spray pond and cooling towers is the fact that in the hottest months when the greatest amount of cooling is needed the relative humidity is also greatest, consequently the theoretical dew point is raised so high that it becomes a rather difficult matter to bring the circulating water temperature down to the required value. In one installa- tion, in order to overcome this difficulty a deep well was driven, and the water supply obtained from this well was practically con- stant all the year at a temperature of 52 deg. Fahr. (11.2 deg. C). To dispose of the water a second deep well was driven and the circulating water pumped back into it and allowed to seep into the ground through the various earth strata. The following figures were used in calculating temperature range for a cooling tower on the Atlantic seaboard : Mean July temperature (deg. Fahr.) 73.0 Mean July wet bulb (deg. Fahr. ) 67 Mean July humidity (per cent) 71 Assuming water leaving the transformer coils at 100 deg. Fahr. (37.8 deg. C), the temperature of water leaving the tower is obtained by substituting in the formula T^ = (T -j- 2fi + 0-^4. t = temperature of atmosphere ^1 = temperature of wet-bulb THE SYSTEM 183 T = temperature of water on tower 1\ = temperature of water oft* tower T,= (90 + 134 + 73.5) -^4 T^ = 74.4 deg. Fahr. During winter weather considerable trouble may be experi- enced due to freezing of the water in the pans, but by installing a by-pass valve and piping so as to utilize only the bottom tray the freezing is eliminated. In conclusion it may be said that the modern up-to-date out- door substation has come to stay and its evolution has gone stead- ily forward. The outdoor equipment is well adapted for furnish- ing both the small rural load and the more important industrial centers. It is far more simple than the indoor type and more space may be occupied with less money expenditure both in structures and equipment, with the resultant advantage that no needless expenditure has been made on useless inclosures and bar- riers. The problem of cooling the equipment has been solved in both the small and large size installations so that it is no longer neces- sary to provide expensive housing for large capacity trans- formers. High-tension insulators, terminals and switches have been de- veloped to such an extent that they may be as safely operated outdoors as when installed under cover, free from the action of the elements. The development of the outdoor substation has been one of the most important factors in the interconnection of high-tension electrical systems and by its means considerable fuel saving may be accomplished in that the most economical generating units may be employed for long-hour use for serving the transmission lines through outdoor substations feeding concentrated industrial cen- ters. In the days of conservation of labor and building material, the outdoor substation was a step in the right direction as its con- struction not only released the experienced labor employed in building construction but also released cars and barges which were used to better advantage in the transporting of coal and other materials which were of vital importance in hastening the victory of the Allies. 184 CUTTING CENTRAL STATION COSTS OUTDOOR SUBSTATIONS SIMPLE AND ECONOMICAL The outdoor substation, according to R. E. Cunningham, Super- intendent of Distribution, Southern California Edison Company, has proved to be the simplest and most economical means of serv- ing large consumers, and the favorable climate of southern Cali- fornia makes its operation entirely reliable. Manufacturers have produced outdoor-type transformers which are entirely satisfactory for all moderate voltages. It has therefore only been left to the operating engineer to select switch- ing and protective apparatus and properly arrange the equip- ment. Most distribution ouidoor substations have been equipped with fused-type switches. The experience of this company with such switches has shown that they are not entirely reliable on account of the inherent weaknesses of high-potential fuses. Par- ticularly on three-phase service is trouble had with one fuse fail- ing, allowing the motors to operate single-phase and in many cases resulting in burn-out of the consumer's equipment. In order to overcome this condition, a local manufacturer has made for the company an automatic outdoor pole-top switch for service on 10,000 volts. The company has more than 200 of these switches now in use, all of them having given satisfactory service. This is a single-tank switch, equipped with three series overload trip coils, so that an overload on any wire of a three-phase circuit will entirely disconnect the service. The switch is controlled b}^ pull cables from the ground, and the consumer can immediately restore the service in case the switch has been kicked out by momentary overload. This saves the consumer a long interrup- tion which would otherwise exist, with the use of fuse switches, since the company would have to send out a troubleman to replace the burned-out fuses. When extra heavy loads are to be started or fluctuating condi- tions are encountered, a simple time-limit device can be attached to the plunger of each overload relay, which prevents the switch kicking out except in cases of actual trouble or continued over- loads. This switch also allows the consumer to disconnect his transformers when they are not in actual use, saving to the power company the energy lost in exciting the transformers and removing all hazard of energized wires on the consumer's property. With a switch of this type on the primary side of THE SYSTEM 185 the transformers installed within 30 ft. (9 m.) of the entrance to the propert}', the local authorities have ruled that the main entrance switch on the secondaries is not required. MODERATE OUTDOOR SUBSTATION The San Joaquin Light & Power Corporation of Fresno, Cal., has an outdoor substation near Madera, in the same State, which may be of interest because of its construction and moderate cost, writes L. J. ]\Ioore, Engineer San Joaquin Light & Power Cor- poration. Suspension construction on wooden poles is emploj^ed throughout. The San Joaquin corporation has always been par- tial to wood poles, owing to its proximity to the Oregon and Washington supply of timber. A quite extensive open-tank creo- soting plant is maintained in Fresno for the treatment of poles which are used on the system. The present high cost of steel was also a factor in determining the use of poles for this sub- station. Other substations which have been erected by this cor- poration have usually been constructed with pin-type insulators on wood poles. All future installations are to be made with suspension insulators, thus making it possible to increase the amount of insulation installed and to secure better mechanical construction than is possible on pin-type insulators. Except for the metering equipment and low-tension oil switches all the equip- ment in the Madera substation was placed out of doors. The substation is connected to a 66,000-volt line which forms a loop through a number of other substations. The transforma- tion ratio is from 66,000 volts to 11,000 volts through a Y-Y bank of transformers with both high-tension and low-tension neutrals grounded. An oil switch and an air-break switch are installed in the incoming and outgoing 66,000-volt lines where they con- nect with the 66,000-volt bus which loops around the substation site. A spacing of 7 ft. (2.1 m.) has been used between high- voltage wires where possible to lessen the occurrence of arcs or trouble caused by large birds flying between the wires. The trans- former bank is connected with the 66,000-volt bus through an air-break switch and an oil switch. Provision is made for seven 11,000-volt feeders, two of which are carried on the transmission- line poles. All 66,000-volt air-break switches used in the sta- tion are five-disk K-P-F switches, chosen because their construe- 186 CUTTING CENTRAL STATION COSTS tion especially fits them for use in this type of substation. A grounding switch is installed on each end of the 66,000-volt lines in order to ground either section of the line in case men have to work upon the line between this station and either one of the two stations adjacent to it. The two grounding switches are mounted eeKV. - iiKv '—Si- ■Tiv> SWITCH 1$) ^'^ISl OiL -> 5WnCH 66KV. at SWITCH \ L.J'. P(MTR TRANSFORMER '^\-:-^ f^ ■^Sh- POTENTIAL TRANSfDRMER <§) ^CURRENT \ \ TRANSfORMER 1 \ T M * T — r — r— i ^ -7 — r " ^ "^ "l "^ eexv "•LINES OF Buiiam OUTDOOR II KV. SWITCH RACK IIKV. UNES Fig. 57 — Electrical Wiring Layout of Modern Outdoor Substation Showing Connections on 66,000-volt pin-type insulators, which are the only high-ten- sion pin-insulators in the installation. The transformer bus is supported on 25-ft. (7.6-m.) poles and is long enough to accommodate two banks of three 500-kva. trans- formers, together with one spare and the controlling switches for both of the transformer banks. The 66,000-volt buses are on the arms across the tops of the poles, and the 11,000-volt buses are supported in a vertical plane on the poles themselves along one side of the structure. The buses are dead-ended in the center of the structure over the spare transformer so that it may be con- nected in place of any transformer in either bank which might become disabled. This location was chosen for the spare unit in order to minimize delay and work in connecting it into service. In the center of the outdoor substation site is a corrugated iron-covered wood-frame building which houses the metering equipment and the 11,000-volt oil switches. All the equipment in the building could and would have been purchased for outdoor installation had it not been for the fact that this type of building adds no more expense than the difference in cost of outdoor and indoor type switches and metering equipment. Also, it was thought desirable to provide a building so that the operator would be near the indicating instruments and the automatic feeder THE SYSTEM 187 switches. If no building were provided, he would in all proba- bility spend most of his time in his home, especially in bad weather, when line trouble would be most likely to occur. The electrical equipment in the building consists of an 11,000- volt bus to which leads from the 11,000-volt side of the station transformers connect through a 300-amp., 15,000-volt General Electric K-12 oil switch and disconnecting switches. Similar equipment is installed on each of the seven feeders which tap off from the 11,000-volt bus. The switches and buses are mounted on pipe framework throughout. The feeder switches are auto- J HI6H TENSION WWW \% ^ (5 Builciing' '■E3-- AA/WNAA \AA/WW ZEIfV i \ 51 [^ [|] .U- Auxiliaiy Bus low tension Fig. 60 — Single-bus System in Substation that Answers the JPurpose OF Double-bus Arrangement THE SYSTEM 195 was not warranted solely by the flexibility it would afford. As an alternative plan a single-bus SA'stem was installed embodying an arrangement of cut-out switches that would permit obtaining about the same results as when a double-bus system was used. The accompanying diagram (Fig. 60) shows the principle used, which provides for the isolation of practically every piece of apparatus in the station without interrupting the service. It is estimated that a saving of about $8,000 resulted from the use of the arrangement which is here described. SECTION III THE SHOP SHOP VERSUS FIELD TESTING OF NEW WATT-HOUR METERS Many central stations, according to George W. Hewitt, meter foreman of the Minneapolis General Electric Company, are ac- tually wasting time and money testing new meters just received from the factory. Virtually all factories ship meters which are guaranteed to be accurate within 2 per cent. Testing the meters in the shop, carting them around all day in a vehicle, often in- stalling them wrongly and not testing again for a year or so induces much "lost motion." "A shop test as compared with a service test, especially on direct-current meters, is not worth the money expended on it," says Mr. Hewitt. In his opinion, the only test worth consideration is that made under actual service conditions. When the commutator of a direct-current meter, for instance, is polished and the meter adjusted it will be found that aging due to the oxidation of the silver commutator affects the meter and that a test made from thirty to sixty days after installation will show different results from a shop test or that made at the date of installation. Then, again, local and earth magnetic fields affect meters to a large extent, depending on the position of the meter. Errors of 5 to 10 per cent sometimes result from this cause. The Minneapolis General Electric Company meter department does 90 per cent of its testing in service, holding its shop testing to a minimum. Meters which are repaired in the shop are ad- justed, within 2 per cent of complete accuracy, and new meters are not tested at all. They are thoroughly inspected and then tested within thirty days after the installation and adjusted to within 0.5 per cent of accuracy. The fact that 95.7 per cent of the installations tested are within the legal limit of 2.5 per cent accuracy seems to bear out the contention that this method of testing is satisfactory. According to the records, only eighteen 196 THE SHOP 197 meters out of 4309 recently installed failed to register. This plan of testing meters after installation has the further advantage of being a check on the men who install the meters. ECONOMICAL PRACTICES WITH METER JEWELS Realizing that diamond meter jewels must be kept in service to justify their high first cost, the Minneapolis General Electric Company places these jewels in each instrument when the instal- lation test is made but replaces them w^ith sapphire when the serv- ice is disconnected. Thus money invested in expensive jewels is not allowed to become idle when meters are placed in stock. The diamond jewels are considered more economical when they can be kept in service because they will withstand 40,000,000 revolu- tions without showing appreciable wear, whereas sapphire will withstand only 700,000 revolutions before wearing out. The extent to which the jewels are lubricated has also been found to affect their wearing qualities and the friction consid- erably. According to a test w4th jewels operating under three conditions — flooded with oil, with only a trace of oil, and dry — the jewel flooded with oil gives the best results and the dry jewel gives the worst. CUTTING METER TEST LABOR The best average record which meter testers of the Crawfords- ville (Ind.) Electric Light & Power Compan}^ could make form- erly, using the ordinary type of testing apparatus, was thirty-five single-phase meters per day. After rearranging all of the appa- ratus into a single compact unit the meter tester was able to average sixty meters a day for a period of ten days. The single- unit set, which is shown in Fig. 61, included the load box and calibrator and all of the connections. F. H. Miller, manager of the Crawfordsville company, said that considerable time is saved by the use of this set because connections do not have to be changed frequently, only about one minute being required to prepare the outfit for testing. Details concerning the construction of the set follow : The out- fit complete weighs 30 lb. (13.6 kg.) and measures 15 in. (38.10 cm.) long by 7.5 in. (19.05 cm.) wide by 10.5 in. (26.67 cm.) 198 CUTTING CENTRAL STATION COSTS high. It consists of a phantom-load box of the type made by the Eastern Specialty Company under the Herman & Mills patent, a Fort Wayne type M2 calibrator and the necessary connections and switches. The load box has a range of 0.25 amp. to 50 amp. of non-inductive load. The calibrator has a range of 1 amp. .[JhCTP hT^ =h Ph Fig. 61 — ^ Wiring Diagram of Combination Load Box and Calibrator to 100 amp. There is a 5-amp. light-load and a 5-amp. heavy- load adjustment. To use the calibrator alone plug No. 1, shown in the lid of the outfit, is inserted to connect points B and C on the wiring dia- gram. To use the load box and the calibrator together plug No. 2 is inserted to connect points A and B and C and D. The plugs are inserted through the holes marked 1 to 100, which correspond to the load desired. Spring switch clips are used for making contacts at the points A, B, C and D. To conduct a test with this set, binding posts A are first con- nected with the service meter, a three-conductor cable composed of one potential wire and two current wires being used for all load conditions and tests. The potential connection is made at P and the calibrator control switch is connected at S. Iron connec- tors are used at P and S. By pushing the plug, in the side of the pendent switch used with this outfit continuous operation is THE SHOP 199 permitted. Pushing the end plug', whieli presses against a spring, causes the calibrator to assume the zero position. REDUCING THE COST OF SOLDERING The cost of soldering lugs on cables, leads or armature wind- ings, etc., has been reduced as much as 60 per cent by the Iowa Railway & Light Company of Cedar Rapids by using an acety- lene-gas torch for this work instead of molten metal or soldering irons. The gas is purchased in tanks and is conducted to the burner used for melting the solder by means of high-pressure rubber hose. This method permits workmen to reach locations easily which would be almost inaccessible with soldering irons, and thus the labor cost involved in the soldering process is re- duced to the minimum. * SPECIAL SWITCH MADE FOR TESTING WATT-HOUR METERS A convenient method of testing watt-hour meters is indicated in accompanying drawing (Fig. 62), writes R. M. Berry. The SOURCZ i? 6, 1 T ^ ih n* .DOUBLE BUTTON PUSH SWITCH J^ LAMP BANK LOAD o va Fig. G2 — Special Switch foh Testi^x Watt-Hour Meters part of the diagram shown at ABCD represents a specially con- structed switch for changing the current coils on the rotating 200 CUTTING CENTRAL STATION COSTS standard without having to remove the wire from one binding' post to the other during the period of testing a meter. This switch has been found to be quite a time saver and helps to eliminate mistakes. The operation of the switch is as follows : For testing with the 20-amp. coil on the rotating standard, adjust the load for 20 amp., throw switches X and Y toward BD and connect points 2 to 3 and 4 to 5 respectively, thus completing the circuit through the 20-amp. coil. In a like manner, for testing with the 10-amp. coil, adjust the load for 10 amp., leave switch Y in position BD and throw switch X toward AC, connecting points 1 to 3 and 4 to 5 and completing the circuit through the 10-amp. coil. In testing with the 1-amp. coil switch Y is thrown toward AC, con- necting points 6 to 7 and completing the circuit through the 1-amp. coil. The idea of having switch Y of the construction mentioned is to avoid blowing the fuse on the 1-amp. coil, as only a definite load can be placed on it. When using the other coils the latter is entirely disconnected. This switch was constructed out of fiber board of ^/^-in. (3-mm.) thickness for the base and standard knife-switch parts for the contacts. This switch can be mounted in any convenient place for shop testing, or a special cover can be made for the rotating standard deep enough to accommodate the switch when the cover is closed. SECTION IV METER READING, BILLING AND BILL DELIVERY, AND COLLECTIONS CONTINUOUS METER READING The llarrisburg (Pa.) Lioht & Power Company has adopted the continuous meter-reading system which will apply to all electrical consumers and is already in operation. A laro^e amount of work was curtailed in the change-over from the old ledger system, but from now on it will make the work of the cashier and bookkeepers much easier. Another very important result of the change will be that it will produce a far better dis- tribution of the crowd in the company's sales office and bring opportunity for more careful selling methods. Under the old system, discount day brought a large run on the electric light office and produced so great a crowd that it was practically impossible to bring any selling influence to bear. From now on, however, there will be a limited number of discount takers in the office every day, and it will be possible to discuss the matter of appliances wdth them. This, it is felt, is certain to produce a large amount of business which otherwise would not be developed. The Beverh-^ (Mass.) Gas & Electric Company also has adopted the continuous system of reading meters and mailing bills, the new plan being adopted owing to conditions created by the war and the necessity for distributing the work as equally as possible for the meter readers and office staff. Under the old plan the bills were read between the fifteenth and twentieth of each month and were mailed out on the first of the succeeding month. The city, which has a population of around 20,000, has been divided into about twenty-four districts. The gas and electric meters in the first district are read on the first working day of each month and bills mailed two days later. The meters in the 201 202 CUTTING CENTRAL STATION COSTS second district are read on the second working day of each month and bills mailed two days later, the meters in the third district on the third day, and so on. Ten days from the date of mailing bill are allowed in which to secure the discount for prompt payment. Discount dates are plainly stamped on all bills. DELAYED METER-READING POST CARDS In order to save the meter readers from the need of making return calls, the Consumers' Electric Light & Power Company of New Orleans, La., Jias devised a delayed meter-reading post DIAL DIAGRAM OF ELECTRIC METER 10,000 1,000 Kilowatt Hours Name Address ■ Dale- You were not at home when our meter- reader called and we ask you to kindly mark on the above dials the exact position of the hands as they appear on the face of your meter, and mail this card at once. Consumers Electric Light & Power Co. Fig. 63 — Meter Reading Post Card Mailed by Customer card. If when the meter reader calls he cannot get in, he leaves an addressed government post card, on the reverse side of which is a dial diagram of the meter on which the customer can mark the meter reading, and on which is also a place for the custom- er's name and address. The customer mails the card and is billed for the amount of energy shown to be used. METER READING, BILLING AND BILLS 203 This S3'stem was put into effect tliere in January, 1918, and as early as May 75 per cent of the cards left were being returned to the company with readings indicated. In July General IManager W. J. Aicklen stated that through the use of post-card delayed- meter readings the company was effecting a saving of approxi- mately $50 a month in meter readers' salaries. ]\Iuch time is lost by the meter reader through customers not being at home w^hen he calls. In order to get around this diffi- culty the Twin State Gas-Electric Company of Brattleboro, Vt., Name._-.. Address . Will you kindly assist us In obtaining a reading of your meter by marking the position of the hands on your meter on the Illustration and mailing us this card. Date of RaadinK _ _ Meter Number.»..._ _ _....- Fig. 64 — Post-card Meter Record asks the customer to read his own meter when the company's reader has not been able to do so on his regular calls. If the meter reader cannot get in, he slips an addressed post card, like the one shown, under the door or puts it in the mail box. This delayed-meter-reading card requests the customer to mark the position of the hands of the meter on the card and mail it to the company. The same consumer is seldom asked to make his own meter reading for two consecutive months ; therefore an5^ inaccuracy in the customer's reading is corrected by the com- pany's man on his following visit. Experience shows that the consumer much prefers this method to having his bill figured on the basis of last year or to being billed for two months next time. Space on the card is provided for the date of reading, the meter number and the name and address of customer. 204 CUTTING CENTRAL STATION COSTS ECONOMIES OF METER READING AND DELIVERY OF ACCOUNTS The employment of high-school students in addition to the necessary regular force to read meters and distribute bills to customers has been practiced for several months past by the Sandusky (Ohio) Gas & Electric Company. This system, the company states, is not only materially reducing the expense of reading meters and distributing- bills, but in addition makes it possible to reduce the re^lar operating force to a minimum, as it has been found that where all meters are read between the twentieth of one month and the first of the next it is not always possible to keep the entire force busy during the period from the first to the twentieth of the month, when no outside construction work is under way during the winter months. BOYS UNSATISFACTORY AS METER READERS The Topeka (Kan.) Edison Company has discontinued its practice of using boys, picked up as temporary employees, for reading meters. The services of the boys in this respect proved to be unsatisfactory and men are taking their places. The men are being employed permanently and do other work when they are not reading meters. A. H. Purdy, general superintendent of the company, expressed the opinion that the company's experi- ence with boys was unsatisfactory because it is becoming increas- ingly difficult to secure, for temporary work, boys of the type needed, since so many of them are engaged in other occupations that pay more than a utility company can afford to give for this class of work. REDUCING THE EXPENSE OF HANDLING ACCOUNTS The Central Illinois Light Company of Peoria, 111., has worked out a system for handling customers' accounts that it believes is particularly adapted to fit its conditions. The system contains features, however, that seem also adaptable to the plans of other companies as measures of conservation. The features of the system lie in the combination gas and electric bill and in the machines for handling ledger work. METER READING, BILLING AND BILLS 205 The company bejian usinti' its present combination bill in Jan- uar, 1917, although combination gas and electric billing went into effect in Jul}^, 1916. J. H. Thomas, chief clerk for the company, writing concerning this bill, said : ' ' The advantages of the com- bined bill as I see them are, first, elimination of the sorting of meter-read slips and bills, thus allowing meter readers to give all their time to meter reading and bill distribution; second, ledger keepers are enabled to post credits, make delinquent notices and draw off balances in one-third less time than formerly ; third, cashiers are able to handle customers faster, as it is no longer necessary for them to add the gas and electric amounts when the bill goes to the consumer with the net amounts extended. Also the cashiers require one-third less time in adding the coupons than formerly." Mr. Thomas continued : In January we replaced our long-hand billing with machine billing, and I consider this a real conservation measure, as our billing force was reduced to one-half of that formerly required. One operator and one stamping clerk now handle 29,000 meters per month. Part of our bills are extended by machine and part by rubber stamps. By test we have proved that extensions may be stamped twice as fast as they could be entered by machine. By analyzing our bills for several months we found that if we used 300 stamps we could stamp about 75 })er cent of all extensions; hence our bill design is such that when the consumption in kilowatt-hours or in cubic feet is in excess of fifty (the limit with the stamps) the extension can be completed by machine. From our ex- perience with machine billing we find that a saving of a})out 30 per cent has been effected in billing expense. The other advantages are a much ' neater bill and a reduction in the time required between reading and bill delivery. Our bill is made out directly from the meter-read slip. We do not make a recapitulation sheet or use a carbon-copy ledger; therefore, of course, do not add meter readings, etc., it being the writer's opinion that this checking is nothing short of a "tail wagging the dog" propo- sition. On Jan. 1, 1918, we also changed to machine-entered ledgers, and with these were further able to reduce our force. I am of the belief that this ledger installation is the first of its kind. We have used it but a short time, but a thorough })reliminarv test was given it. Actual working has maintained the results of the test. By its adoption we have been able to reduce ledger costs 30 per cent. 206 CUTTING CENTRAL STATION COSTS HANDLING BILLING IN A CITY OF 70,000 Two youths aged about eighteen deliver the 23,000 monthly bills of the Kansas Gas & Electric Company at Wichita, a city of 70,000 inhabitants according to the 1910 census. These boys are paid from $45 to $50 a month. When they are hired they are told that the position is permanent and affords them an oppor- tunity to work up to the next position, that of meter reader, which pays $65 a month with a 10 per cent commission on all appliance sales made. When the bills are ready for delivery they are first routed by ALWAYS PRESENT THIS CARD WITH PAYMENT KANSAS GAS & ELECTRIC COMPANY OiGoc Houra 8 a. m to 5 p m. i 1 1 i 1 S FLAT RATE POWER Light to Sign to Conaqmed- IQO K. W. Hra at le... 100 K. W Hra at 6c... 100 K. W Hri at $e... 200 K. W. Hra. at 4c... 1000 K. W. Hra. at 3Me UOOK. W Hra.at3e... ..atlHc Total Plat Rale. '^OMMEPCIAL LIGHTING R«ad .. j Read .. |_ Conaumed- K W Hra. Q^ K. W. Hra. at t'Ac K. W. Hra. at «c .. E Total Powe Total Plat Rate _ Toul Commercial UnS«U»aMra«rb 0\0 K\O>0\l«N'r<- l^\.Hl«^^\l»• «-• HN lO 'OvrwOr4«QiA(7v .•^o 8^ N'HMN*^ »4»<NC\i Oi kNj (^ (ft '^ w f>^ OM <\J »H -• CVJ CM r» loj ^ g\ ir» »< y* cA o 5» in o- /ir» K\ »< M CM <-• vo O) O N»NO O r^.'O r< o Nr^ n 1-1 in K^ e\ ^^ fvj ^ cv CM > H CM r^ r» I »H»^ i-iOO OOO 0*0 r-t f^ v\ f<> •.^ in -"^ l« Mil b.ram.f drllOilUtat •< Ool Mkl m or brl.r, in. u.lti Minimum b.ll. Uk Brt 1 1 Pt£ASE BRING TWS NOTICE THE HYDRaElXCTRiC UGHT AND POWEK Ca roB ELEcnuc towib ficsvici J. P. BT MSTEB eTATUiEtr ' OBUKttfl LiMd D»t« B*»aiat _ 1 MaxlBon Dmud .„ K.W.xlJ« = rw aj laxairv ep«ilu i: w H l' ut, a—L xwa»..< ::- 1 «- Df««xjQt .D thii bill *IJI br .liowf^ LtMt 5% Ob tatrtj Cbvft ■ ■nifj blU bttomn dflibgwot It not BoIum Uopbtd ■ - • 1 T MJDlmuiDblU-tb«duiiui4d>.rf.-bcL ToUl .... o o PLEASE READ THIS. If you discoDDt your electric blUi tbis doe« not apply to 70U. BUT-'-li you let your account go delinquent, we want you to read tbl* carefully. KOA By diMounilnf your b.lli before the lOih. you uve one morith'i bill during the jeir. BUls become delinquent. If not paid on or before the Ittta oT month following rendering of service, In which case, after due notice, service may be discontinued and a charge of SI. 00 will be made In ad* vance for reconnecting. Plejw «e ihji voiir .ccount it p.».d promptly e.th month ind do n« bliOK lu it your llihi, .rt d.,tonn,ttcd (or nonpjymrni We e.nnoi diKnm.n.ie. We muU Otkc The Hydro-Electrjc Light & Power Co. Fig. 08 — The Three Bill Forms Used by Indiana Central- Station Company the consumers' premises. The company supplies electric light and power service as well as gas in Connersville, which has a population of 8000, and also supplies electric service to several small towns near by. The general form of bills is the same for each class of service, namely, electric light, electric power, elec- tric service in nearby towns, and gas. The bills differ somewhat, METER READING, BILLING AND BILLS 211 however, in detail. The three types of electric bills, which the company desionates as forms Nos. 107, 108 and 109, are shown in Fig. 68. Form No. 107 is the regular lightiim' bill, form Xo. 108 is the regular power bill, and form No. 109 is the bill which is used for small towns where collections are made through the banks. The system as it applies to form No. 107 is as follows: The bills are made in triplicate and are perforated for easy detachment. An addressograph is used to fill in the name, ad- dress and date. The last readings and any balances are then put. on. The meter readers aim to read 100 bills each half day and have ring binders which will take care of that number of bills. As they read a meter they make out the bill and leave the third copy, bringing back to the office the copies marked "File" and "Receipt." Postings are then made, and the bills are dis- tributed in an office rack for payment. When payment is made the customer is supposed to bring with him the third copy. This gives the account number, which is also put on by the addressograph along with the name, etc. This plan facilitates the locating of the original bill, but, of course, is not absolutely necessary. The company's cash register prints the receipt on the right end of the customer's copy, showing who receives the payment, the account it goes to, the amount, the transaction number and the date. The same information is also shown on the margin of the company's own copy, which is filed for future reference. The same system applies to the power and gas bills, but the form No. 109 used in small towns is slightly ditt'erent. The difference is that the customer brings back his notice to be re- ceipted, whereas for the city customer the second office copy is receipted. In the small town meter readers leave one notice at the house, a second notice at the bank and bring back the first copy to the office. In response to a query about the cost of operating this system, Erie G. AYeeks, treasurer of the company, said: "I have no absolute costs, but our men can read 200 meters a day. This gives an idea of what the cost would be. We consider that the expense of getting the bills ready would be no more than that of any other form of billing. "There are several very distinct advantages in the use of these bills. First is the saving of postage. Second is the fact that 212 CUTTING CENTRAL STATION COSTS the customer can come in and pay his bill just as soon as the meter is read. There are many cases where the customer comes into the office to pay his bill before the meter reader returns after the half day, and since the customer has his own copy of the bill we take his money and get the benefit of the use of it. During these days of close figuring we feel that this early collection is worth something. ' ' Then, again, we have the use of the advertising on the back of the bills. This is not a big expense, and the announcements go to every customer, giving us an opportunity of pushing a special item each month. The copies shown, however, can hardly be said to carry an advertisement. We wanted to urge prompt pay- ment. ' ' RUBBER STAMPS SAVE EXPENSE The Consumers' Electric Light & Power Company of New Orleans has introduced a system of rubber stamps to save some Fig. 09 — How Public Utility Uses Rubber Stamps to Save Billing Expense of the clerical work entailed in making out its several thou- sand monthly bills. Under the company 's rate lighting service is METER READING, BILLING AND BILLS 213 figured on a slidino- scale and a g:reat deal of calculating is re- (juired in figuring the bill totals each month. To make out a bill for 800 kw.-hr., for instance, it has been necessary to list tive amounts and the total, including, first, the service charge of 25 cents; second, the first 20 kw.-hr. at 8 cents; then the next 30 kw.-hr. at 7 cents; then the next 150 kw.-hr. at 6 cents, and the final 100 kw.-hr. at 5 cents. These extensions must then be totaled. A careful analysis of the bills developed the fact that 80 per cent of the customers were using somewhere from 1 kw.-hr. to 300 kw.-hr. per month, and a series of rubber stamps were se- cured numbered from 1 to 300, each of which bears the necessary calculation to cover that consumption. So that by merely stamp- ing the bill the fixed service charge of 25 cents, which is added to all retail bills, and all the items on the sliding scale are covered in one operation. The billing clerk has these 300 stamps before him arranged in a handy rack, from which he can easily pick the proper stamp with far less risk of error than in hasty figur- ing. The only figuring now necessary on the bill in pen and ink is the discount allowed for prompt paj'ment, a simple matter as 1 cent is allowed for each kilowatt-hour consumed during the month. It has been found that the use of these stamps makes it possible to do the billing in one-third of the time formerly required, and with considerable more neatness, besides minimizing the element of incorrectness in totaling. General Manager Aicklen recom- mends this system to other managers and offers to send a full set of impressions from these stamps to any one who desires them. POSTAL CARDS FOR BILLING In many ways government postal cards present a means of saving in billing. For one thing, the stock costs nothing. A number of central stations have come around to the use of postal cards for bills. The Oklahoma Gas & Electric Company at Kiefer and the Sapulpa (Okla.) Electric Company, under the management of H. M. Byllesby & Company, use similar cards, as shown in Fig. 70. Dates and the space to the right are in red and are changed each month, and the space at the left is used for advertisements and announcements. 214 CUTTING CENTRAL STATION COSTS TO OKLAHOMA GAS & ELECTRIC CO. DR KIEFER, OKLAHOMA <;Fr 1 INF DEC. 1917 KIEFER. OKLA ELECTRIC CURRENT FOR DECEMBER 1917 Our Wish for You A Very Prosperous New Year DEC READlNf, KWH CONSUMPTION Kwu DISCOUNT lO PER CENTir PAID ON OR BEFORE -'"'^ '° 'S'" NET AMOUNT MINIMUM BILL. NO DISCOUNT DELINQUENT BILL NO DISCOUNT TOTAL BRING THIS CARD. PLEASE. TO BE RECEIPTED FAILURC TO ntCCivc BILL DOES NOT ENTITLE CONSUMER To DISCOUNT 6000 SERVICE 'O »Ll CONSUMEMS SENDTHISSTUa WHEN YOU REMIT BY CHECK Fig. 70 — Postal Card Bills Have Their Owx Advantages GAS AND ELECTRIC BILLS ON SAME POST CARD While the post-card bill has been used rather extensively by both gas companies and electric companies, it is rather unusual to find a combination gas and electric company placing both To FORT SMITH LI6HT fc TRACTION CO. Dr. FOMT SMITH AND VAN BUREN. ARK. APRIL, 1918 APRIL, 1918 UAS: April Reading March Reading Cubic Feet Used 000 Net Should Injunction be diaaoloed and 17-cant rat* applp. poa will be entitled to a refund on thia bill of r CAS CA3 ELBcrruici April Reading . March Reading , Gross Difference . Disc. ELECTRIC ■lLECTRIC X : K.W.H. Used Net Previous Balance TOTAL To receive discount, bills must be paid on or before the 10th of month following that in which service is rendered. Failure to receive bill does not entitle constuner to discount PLEASE BRING THIS CARD Mail end with this check Fig. 71 — Combination Bill of Arkansas Company electric and gas bills on the same post card. This practice, how- ever, has been resorted to by the Fort Smith (Ark.) Light & Traction Company in an effort to keep its billing costs as low as possible. The accompanying illustration (Fig. 71) shows how the readings and the items indicating cost of service are arranged on the card. It is the intention of the auditing department of the company to add a place on this post-card bill later for mer- chandise accounts, thus further reducing the number of different METER READING, BILLING AND BILLS 215 forms used by the company to cut down billing expense. Tlie company has about 4010 electric meters and 6459 gas meters, making a total of 10,469 meters in service in the two cities of Fort Smith and Van Buren which it serves. RECENT METHODS OF BILL DELIVERY With the thought and energy of every central station concen- trated as never before on measures of economy, a great many companies have turned a searching eye on their methods of deliv- ering the monthly statement. The increase in the postal rates has brought a considerable additional cost in many cases, and the loss of men into the national service has generally reduced the organization available for carrying on routine v^^ork of this kind. When the postage rate went up, of course, the idea of discon- tinuing the mailing of the monthly service bills and delivering them instead naturally suggested itself. There is more than the question of cost involved, however, for the mailing of a bill is generally conceded to be satisfactory proof of its delivery. Moreover, if delivered by hand, should this be done by meter readers, high-school boys, old men, girls or women? Or, if mailed, which is the better — post-card or regular bill inclosed in envelope ? These questions are particularly pertinent and worth consideration by every central station. Not long ago — but before the postal rates went up — the Cleve- land Electric Illuminating Company made an analysis of the cost of its bill delivery, which includes 60,000 bills delivered by hand and 40,000 by mail, to find out how much could be saved by using a post-card bill. The figures were found to be as shown in the accompanying table. AVith the 1-cent postage rate the post-card proved to be the cheaper method, but the doubling of this cost made the hand- delivery system far more economical. The system in Cleveland has been to place the delivered bill in the consumer 's mail box, or if there is no box to hand it to a member of the family. Failing this, the distributer brings back the bill and it is mailed. For this delivery the Cleveland company first tried boj^s sixteen or eighteen years old, but did not find them satisfactory. It then employed elderly men of from fifty to sixty-five years and has practically eliminated all complaints. 216 CUTTING CENTRAL STATION COSTS In Sandusky, Ohio, however, the Sandusky, Gas & Electric Company has had most satisfactory results from high-school boys, who both read the meters and deliver the bills. The boys receive 1 cent per meter read. Before the postal rate went up the company used government post cards, but since then it has de- vised a card of the same size, of which a six months' supply can be printed in advance. These are stamped and mailed to customers beyond the convenient reach of the delivery routes, but the bulk compaeison of cost of present system of handling 100,000 consumers' Bills per Month with Proposed Special Card or Government 1-Cent Post-Card System, at Cleveland, Ohio Present system, printed bill in outlook envelope; 60,000 delivered by company distributors, 40,000 mailed with 2-cent stamps. present SYSTEM: 100,000 bills, at $1.50 per 1000 $150.00 100,000 outlook envelopes, at $1.65 per 1000 165.00 40,000 2-cent stamps in rolls 802.40 Inclosing bills in envelopes — 2 boys one month at $40 each 80.00 Sealing 100,000 envelopes and affixing 40,000 stamps, one boy one month 45.00 V Sorting 60,000 bills for delivery, one boy one month . . 40.00 V Delivering 60,000 bills, live men at $70 per month 350.00 Supervising delivery, half time of one man at $100. .. . 50.00 Total $1,682.40 proposed SYSTEM: Special Cards, 1-Cent Post Stamp A^xed: 100,000 cards, printed $116.00 Affixing stamps, one boy one month 45.00 100,000, 1-cent stamps, in rolls 1,006.00 Total 1,167.00 Amount saved by using special cards and affixing stamps $515.40 Government 1-Cent Post Cards: 100,000 cards $1,000.00 Printing 25.84 Total $1,025.84 Additional saving with government cards 141.16 Amount saved by using government stamped cards $656.56 Items checked V indicate expense of delivering 60,000 bills per month. To find total delivery expense on 100,000 bills, add item No. 3, 40,000 2-cent stamps, $802.40. METER READING, BILLING AND BILLS 217 of them the boys deliver at a cost so far of approximately a half cent per bill. This the company finds is effecting a saving of $18 per 1000 customers per month on postage alone and is bring- ing additional economy by reducing the operating force to a minimum during the winter. Because of the limited number of hours that the students have available for this work, it is neces- sary to employ a much larger number than if the regular em- ployees were handling it, but this has not proved an objection. About 9000 bills are delivered in Sandusky between the twentieth and the last of each month. In Mobile, Ala., the company now delivers by hand at a cost of about V/i cents per bill, a saving of about $37.50 a month since the postal increase. In Traverse City, Mich., the company deliv- ers to about 1400 consumers at a cost of 1 cent, and this also includes collecting about one-third of the accounts. In Pine Bluff, Ark., the company delivers 4500 bills, using the regular meter readers after the readings are completed. It requires from four to five days and costs in all, it is figured, from $10.50 to $12.50. In Kokomo, Ind., the company has also changed from mailing to delivery and is distributing 6000 bills by meter read- ers at a cost of $35. In Kingston, N. Y., the meter readers now deliver 5800 gas and electric bills, all except about 300 which are mailed to outlying territory, and the company finds the system quite as dependable as by mail. It saves approximately $50 every month. In Indianapolis the meter-men of the Merchants' Heat & Light Company read meters every morning and deliver bills in the afternoon, and the}' have proved much more respon- sible than schoolboys, though boys were tried. The cost per bill now figures about 1 cent. In Denver the bills are mailed to the suburbs but delivered in the city by boys and young men on bicycles at a cost of one-third of a cent per bill. In Wilkes-Barre, Pa., 19,500 bills — gas, electric and steam heat — are delivered by two men, who receive $65 per month, deliver- ing continuously, which means a cost of about one-half cent per bill. These men collect when possible as they deliver. In Terre Haute, Ind., the company formerly had mailed all bills at a total cost of $125 monthly, but with the higher postal rate began deliv- ering all bills within the city by one man, who is paid $45. The remaining postage cost for bills still mailed is also $45, so that in spite of higher postage the company is saving $35 monthly. 218 CUTTING CENTRAL STATION COSTS The consensus of opinion, therefore, judged from the experi- ence of these and a large number of other cities heard from, would clearly recommend the delivery of bills within the centers of dense population. One Pennsylvania company, moreover, which operates through an extensive rural territory serving about 75,000 population, is delivering all bills in spite of distances, and claims a deliver}^ cost of 0.92 cent per bill on a total of 7016 bills. This company lays much stress at the same time on the value of the collectors in maintaining good relations with the consumer, a point which is echoed by a number of other companies. Men are picked who do their work in a friendly spirit, and much good comes of it. On the other hand, in many outlying towns in Indiana the Indiana Railways & Light Company began with this year to try the plan of not sending any bills at all to some 2000 customers, who are asked to call at the local offices to pay their bills, though delinquency notices are still mailed when necessary. In line with this, in Brattleboro, Va. ; in Franklin, Ind., and in Seymour, Ind., the local utilities have been furnishing many customers with cards on which to make their own meter readings. This method has met with considerable success. In Fort Madison, Iowa, the meter reader in certain residence districts carries with him bills already partly made out, on which he enters the read- ing, making out the bill and presenting it for collection at the one call. The company's other bills go out on post cards, and, in short, since the rates went up there has been a decided move- ment in the industry toward the post-card bill as offering an appropriate war-time economy. Few Companies Using Women. All in all, however, the trend is toward delivery, if not by meter reader, then by boys or old men. One New England central station has found a prac- tical solution by making use of the services of the substitute post- men, who, though on waiting orders, are familiar with the town and have received instructions in delivering. Everywhere the possible expedient of utilizing women for delivering has been con- sidered, but apparently it has not been adopted very largely. However, El Reno, Okla., reports the bill delivery in charge of two young women, who are taking care of it well and at a saving of $30 monthly on postage. At Binghamton, N. Y., girls are used to read meters and deliver bills. METER READING, BILLING AND BILLS 219 Of course, the many cities where bills have always been mailed at the 2-cent rate are not affected by the postal increase. Buffalo and Wilmington, Del., state that they have no intention of chang- ing, for they consider mailing less trouble and more sure. In Detroit, on the other hand, the company has been delivering bills by messenger for years at a cost much less than postage, the meter readers delivering the bills. In Providence, R. I., the method is optional with the consumer in most districts. He may have it by mail or messenger, as he prefers, and bills for suburban towns are delivered to the suburban pont offices and mailed there under the local rate. There is plainly enough diversity, therefore, to suggest the advisability of every man looking well to his own conditions locally; but in the majority of cases delivery seems to be the preferred method. ECONOMY IN BILL DELIVERY Phases of operation, such as the distribution of statements, which during pre-war periods received only passing attention, are demanding greater consideration, writes 0. M. Booher, chair- man commercial section Indiana Electric Light Association. All unnecessary expense is being eliminated and all necessary ex- pense is being reduced. Long-established customs are now giving ground to different and more economical methods. This is especially true in the distribution of bills. During the pre- war period a very large percentage of this work was handled by mail ; to-day many companies ask their patrons to call at the office for their statements, and many others deliver their state- ments in person. ]\Iost of these changes of methods have taken place at least since the recent increase in postal rates. The acid test of a plan is the way it works out in practice. From the standpoint of economy a certain arrangement may be fine and at the same time prove to be very impracticable from other angles. Considering the plan of bill delivering in person, there arises the complaints from customers who are displeased because of not receiving the statement regularly or receiving the wrong statement, etc. Another phase of this plan which must be considered is the general public opinion regarding the evasion of the war revenue which would be derived from the increase in postal rates. 220 CUTTING CENTRAL STATION COSTS The Indiana Railways & Light Company believes the saving effected by personal delivery more than offsets a few scattered criticisms and complaints which are heard from time to time from the customers. During the pre-war period it was mailing its bills for the exact cost of $11 per 1000. This includes postal cards and printing. It is to-day delivering in person at a cost of $10.60 per 1000, including paper stock, printing and labor. Had it continued to send its statements out by mail the cost would be $21 per 1000. In other words, the company is saving $10.40 per 1000, and for 8000 accounts a saving is realized of $83.20 per month, or approximately $1,000 per annum. The labor item figures 0.74 cents per statement delivered. The state- ments are delivered by the metermen. Mr. Booher is of the opinion that, considering the utility as a highly important war-time essential, the operators are perform- ing a patriotic duty in trying to maintain financial equilibrium in order that the utility may continue to remain a valuable war asset. And if $1,000 per year can be saved by changing this or that operating plan, the change should be made, for such a change would be more in keeping with the general war pro- gram than the purchase of a few postage stamps, which net the government an infinitesimal profit. Questionnaires were forwarded to forty-three leading member companies of the Indiana Electric Light Association, represent- ing fifty-six different properties. Twenty-eight replies, represent- ing thirty-nine properties, were received. The first question was, *'Do you deliver by mail, in person, or are bills held at office?" There were thirty-four replies, divided as follows : By person, 15; by mail, 8; bills held at office, 11. One reported that bills were made out and left by readers. Question number two asked for the cost per statement delivered by person. There were twelve answers. The average was 0.89 cent each. Question number three asked, ''Do you have many complaints from cus- tomers where bills are delivered in person?" All answered, ''A few." In seven cases the meter readers did the delivering, in two cases office clerks, in two cases young boys, and in one case an office girl. It is of interest to note that where boys were used the cost per statement averaged only 0.49 cent each. Because of the scarcity of men no doubt many companies which deliver the bills in person are considering the employment of METER READING, BILLING AND BILLS 221 women. So far as is known, this arrangement is not in use at this time to any extended degree. When the time comes there is no doubt that women will prove capable not only to deliver state- ments but to read and test meters and perform many other simi- lar duties. Another plan which might be considered is that of placing bill delivery in the hands of outside agents. In some cases agents may contract with all other local utilities for the per- formance of this duty and consequently be able to make a very attractive price. IMr. Booher feels, however, that the work should be done by men inside of the company in order that all irregularities may be properly looked after. From the replies received from the various companies regarding bill distribution it would appear that this question has not received proper con- sideration in some cases, or that there exists a wide difference of opinion. ''CASH-AND-CARRY" PLAN APPLIED TO LIGHT BILLS Lighting companies operating in small communities have been under a greater comparative strain during the past two years than those operating in larger places. With little opportunity to increase their load, with fixed rates and the increasing cost of Electric Light and Power Bills Will be ready for distribution at the Company's office January 1st We are discontinuing the old practice of delivering bills, and will be pleased to have you cooperate with us by calling for your bill promptly. Respectfully^ Fayette County Utilities Go. Fig. 72 — Advertisement Used to Announce Change in J3illing Method 222 CUTTING CENTRAL STATION COSTS operation, these small companies, which never did as a class enjoy an enviable net profit, have been hard pushed these days to show any profit at all. To prevent disaster economies must be put into practice wherever possible. A single example of an economical measure particularly adaptable to the small-town property is out- lined below. It is a method for cutting the cost of billing. Several subsidiaries of the Utilities Development Corporation of Chicago have discontinued their old practice of distributing or mailing bills for electric service to consumers. Instead they now advertise that the bills are ready for distribution at the company's office and request customers to call for them. The companies which have tried the plan, according to Miss L. M. Beefield of the Utilities Development Corporation, are enthusias- tic over its success. The Fayette County Utilities Company, Oelwein, Iowa, one of the subsidiaries using the plan, reports that in November the expense of sending out the bills was approximately $18.65 under the former method, and this represented the situation generally throughout the industry. This figure included payment of 1 cent per bill to the high-school boy who delivered the majority of the bills, besides the cost of envelopes, labor of folding, inclos- ing, sealing and stamping the remainder, plus postage. In De- cember, under the new system, the expense was only $7.50, namely $2 for the advertisement and $5 for postage on the bills which were not called for, plus about 50 cents for the envelopes. Seventy-five per cent of the bills were called for by Jan. 15 after the advertisement (Fig. 72) that made the announcement as of Jan. 1. A far greater proportion of bills called for is expected in succeeding months, inasmuch as many customers failed to notice the advertisement and were awaiting the receipt of their bills by carrier. In commenting on the plan the Oelwein company stated : ''As a labor-saver the plan is a wonder. It does away with the fold- ing and inclosing of the bills, together with the sealing and stamping of envelopes, and we certainly appreciate this extra time along about the latter part of the month ! ' ' In trying out this plan, however, a word of caution is neces- sary. If a customer does not call for his statement, he should be billed. Otherwise a customer might get two or three months in arrears and find it difficult to make a settlement. In such a case METER READING, BILLING AND BILLS 223 not onh' does the coinpaii}' stand to take a loss which might wipe out the saving of a whole month but it is also likely to make an enemy. SPEEDING UP COLLECTIONS It appears the question of collections looms large, partic- ularly at this time, when every dollar must be worked and worked to the limit, writes O. ]\I. Booher, chairman commercial section Indiana Electric Light Association. The usual custom of having the local central station serve its community in the capacity of a bank, without proper banking rules and regulations, is poor business, even when money is easy. The tightening up of money naturally should lead the central station to think of means to hasten collections. The practice of time payments on mer- chandise and miscellaneous sales accounts should be either en- tirely eliminated or greatly reduced unless a fair rate of interest is collected or unless the sales profits are amply sufficient to war- rant time payments. Reconnection Charge Should Be Enforced, All companies should establish and enforce without discrimination certain pen- alties for non-payment. In extreme cases, W'here disconnections are necessary, a charge for reconnection is not out of place if the ''chronics" are to be eliminated. There has been enforced in Kokomo, Ind., a reconnection charge of $1 and it is found that it adds materially to collections as a whole, helping to reduce non-collectibles to less than 0.5 per cent. Little adverse public comment is caused by this practice. Another feasible plan which is working out successfully, especially with the larger companies, is the establishment of authorized agencies in each small community center where all bills save those in dispute or in arrears may be paid. Such a Replies to Questions Asked of Forty-eight Electric Companies Number Averaj^e of Answerinf^ Yes No Answers Do you allow cash discount 37 28 9 ... Do you send out delinquent notices. . . 30 30 Do you discount for non-payment after a certain date 36 34 2 Do you char*?e for reconnection 38 17 21 Per cent, of bills collected durinpr dis- count period 31 . . . . 78.5 Per cent, receiving delinquent notices 30 . . . . 11.2 Per cent, of total monthly receipts considered non-collectible 24 . . . . 0.87 224 CUTTING CENTRAL STATION COSTS system adds much to the convenience of the customer and speeds up collections considerably. At the same time it creates public good will. The question of collections is closely affiliated with public policy. Labor is scarce and its scarcity is increasing, conse- quently labor is growing much more independent. A man can be loyal to his company or disloyal as he chooses. He can get a job just as good, or maybe a little better, somewhere else. Therefore great care should be exercised in the selection of a man to place in charge of collections, so as to be sure that the company's interest will be carefully looked after. The customer should not be antagonized or insulted because he is a little late paying his bills. In other words, proper discretion should be exercised, and this will not be done unless a man of acquaintance and one who is in touch with the public pulse be employed. How Thirty Indiana Companies Do It. In order to sum- marize the collection practice of a number of companies letters were sent to forty-eight members of the Indiana Electric Light Association. The replies received are reviewed in the table here- with. These replies show that a majority of companies favor allowing cash discount, sending out delinquent notices and dis- connecting promptly for non-payment. Opinion seems to be about equally divided for and against a charge for reconnection. The replies also show that 78.5 per cent of the customers take advantage of cash discounts and 11.2 per cent wait to receive delinquent notices. The average of accounts considered non- collectible amounts to the surprisingly high figure of 0.87 per cent. The letters also brought out that in thirty-one companies the collections are looked after as follows : Two companies by man- ager of collections, five companies by chief clerk, eight companies by cashier, two companies by auditor, seven companies by office force, six companies by general manager, and one company by treasurer. In most cases the same individual looks after collec- tions of accounts for merchandise, motors and signs as well as customers ' monthly accounts for energy consumed. METER READING, BILLING AND BILLS 225 GRANTING CREDIT When every dollar means so much, when losses must be min- imized, the necessity for stricter credits becomes apparent. The credit department of a central-station company therefore occu- pies a much more important position than formerly. Strict methods calculated to keep down losses are all the more desirable. Such methods are outlined in the following statement showing how a large Middle Western utility takes care of its customers' credits. Two Classes of Contracts. Commercial contracts are re- ceived in the credit department from the contract department, and on receipt are stamped on a receiving time stamp showing the exact time of arrival in the department. They are then checked off in a receiving book, which is an index as to whether or not the contracts have been received or are being held in the department. The credit slip attached to each contract then receives a number similar to the contract, by which it can be identified later on should it become necessary to refer to it. After a careful exami- nation of the signature on each is made, the contracts, which may be divided as class 1 and class 2, are handled in the following manner : Class 1 — Applications from those claiming to be former con- sumers and giving address of former location as reference. The account is looked up to ascertain the customer 's habit of pay and to find out whether the account is paid up to date. If the inves- tigation proves satisfactory, the application is passed without further delay. If, however, the customer has paid penalty month after month, or if it has been necessary to cut off his service in order to force payment, a deposit for the new address is required. When a deposit is necessary the customer is so notified by let- ter and the application is held pending its receipt. Upon receipt of the deposit a deposit certificate is issued and mailed to the de- positor and the application is approved for service. When more than the current bills at the previous address are found owing a statement is sent the customer, with a letter notifying him that no service will be given until payment is made. The account in arrears is noted ''Notify credit department when paid," so that in the event of the payment crossing the letter in the mail, the 226 CUTTING CENTRAL STATION COSTS bookkeeper will advise of receipt of payment at once and thus avoid unnecessary delay. The application is filed in the holding file, and no service given, until account is paid. Class 2 — Applications from those claiming never to have used company 's service. This class of applications is looked up in the suspense file to ascertain whether the applicant has not over- looked a previous address where service has been used and a bal- ance remains unpaid. If the suspense file discloses such an account, the applicant is advised by letter of such indebtedness and payment requested, the application being held and no service given until payment is made. Duplicate Copies of Applications. When the suspense account discloses no indebtedness, rating books are consulted, in some cases special reports from the rating agencies are obtained, or references offered as to the responsibility and credit standing of the applicant are investigated. Should the investigation prove unsatisfactory, a deposit is requested which is equal to two months ' bills, the amount of the bills being estimated by installa- tion, location and class of business. This deposit is requested by letter and the application filed in the holding file until received. Owners of real estate in good standing are passed after claim of ownership has been verified. Applicants who object to mak- ing a cash deposit can furnish a guarantee from a real estate owner in good standing, or from a responsible business man, guarantor being required to sign a form adopted for this pur- pose. A duplicate copy of all resident applications taken in the con- tract department is received in the credit department each morn- ing. On these applications the service has been given before the credit has been passed so as not to inconvenience the applicant while credit is being investigated. On receipt of these duplicate copies of the application the same routine is followed as with the commercial contracts. When deposits are required which the applicant refuses to pay service is disconnected and the meter re- moved in a manner to be explained further along. All letters requesting a deposit or unpaid balance have two carbon copies. One of these copies is attached to the applica- tion and filed in the holding file and the other is filed in an every-day file seven days after date. When these copies are reached they are checked with the holding file, and in all cases METER READING, BILLING AND BILLS 227 where the request has been complied with the copies are de- stroj^ed, but those from whom there has been no reply receive a second letter calling attention to the first one and requesting a reply. These second letters also have two copies, one of which is attached to the application and returned to the holding file, and the other placed in the every-day file seven days ahead. If no response is had to this letter at the end of seven days, the application is removed from the file, and if the applicant has no service at the new address it is canceled and returned to the contract department. Where a deposit is found to be necessary from applicants for commercial lighting who move into a location where light is already installed and in use, and for all resident applications where service has been turned on before credit is investigated, a shut-off notice is made out at the time the first deposit letter is written. This shut-off order instructs the shut-off collector to call and obtain the deposit or disconnect the service. When the collector calls, unless deposit is received or a good reason given for its not being made, or satisfactory information as to the applicant 's credit standing given, service is discontinued. These cut-offs are held ten days, and if the applicant does not call or make some attempt to satisfy credit, the meter is ordered re- moved. When the repair department reports back that the meter has been removed the application is canceled and returned to the contract department. In all cases where commercial applications are held in the credit department the contract department is notified at once why application is being held, and in cases where the applicant is the successor and the service has not been discontinued for the prede- cessor a status slip accompanies the notice requesting that the successor be billed from the date of his application. When a final bill is rendered and not paid a statement is made out in duplicate by the collection department and a duplicate copy is sent to the credit department, where a record is taken of it on a card and the card then filed in the suspense file. Where the delinquent is a corporation or partnership the credit slip received with the contract is referred to, and the officers' or part- ners' names and addresses are ascertained and a card made in each of their names, with a notation thereon to refer to the card for the company of which they are members. The dupli- 228 CUTTING CENTRAL STATION COSTS cate statement is then stamped "Suspense" and returned to the district head in charge of collections, to be used as a check on the collector. The statement is then worked by the collector, and a report of his calls and their results is noted on the reverse side. Should the statement be collected or paid at the office, the statement is returned to the credit department so noted, and the card is withdrawn from the suspense file and destroyed. Should the account prove uncollectible and it be found necessary to send to an attorney, the statement of the collector, with his reports noted thereon, is returned to the credit department and any in- formation of value obtained by the collector is transferred to the suspense card to aid in the collection of the account later if opportunity arise. The value of the suspense file depends in large measure on ob- taining the applicant's full first name. If the customer insists on signing the first initial only, he may be allowed to do so, but effort is made to find out what the initial stands for and to note this on the application. The number of suspense cards made out and filed by this company averages approximately 3500 per month, and the average monthly revenue obtained from this file during the past year amounted to $800, or almost $10,000 in the course of the year. Handling Merchandise Sales Orders. Merchandise sales or- ders are handled as are light and power applications. Many firms are trading on open account with this company, and some accounts must be watched closely, letters being continually writ- ten requesting payment on slow accounts, and in a few cases credit being stopped completely pending settlement. A card file is kept in the department showing customer's name, service location, date signed, the predecessor's name if it is a successor application, the name of the company's agent obtaining the business, and the order number of the contract, which num- ber agrees with the number on the credit slips. Another file is kept which shows all deposits of record, by whom made and for what address, and still another file for line extension advances, which are taken by the credit department and either applied on the light and power account, if the customer is a consumer, or transferred by journal entry to a holding account. Granting Credit upon House-wiring Contracts. On receipt of a house-wiring contract the name and location are entered METER READING, BILLING AND BILLS 229 •ill the receiving book, and a number is o-iven as a means of identification. The location is then looked up through a firm employed for this purpose to see if the applicant's claim of ownership caii be verified, the credit data are checked, and ref- erences are investigated as in commercial and residence con- tracts. If the investigation shows the applicant to be a good credit risk, holding title to the premises where the work is to be done, and the relation of the encumbrance to the valuation is not excessive, the contract is approved. If, however, the appli- cant is found to be buying the premises on contract of recent date and his equity therein is not sufifiicient to warrant the instal- lation, the holder of title is urged to sign the contract jointly with the applicant. Should the records show the applicant to be buy- ing the property on contract which has extended over a period of years and upon which a substantial sum has been paid, the owner of record is requested to sign a rider giving date of the contract of sale, the amount involved in the contract, the amount the applicant has paid on same to date, and permission to the company to install the wiring, which permission carries the stip- ulation that all bills are to be paid by the applicant. Contracts of this nature handled by this company average in price, includ- ing fixtures, from $60 up, most of them being around $200, but occasionally single contracts amount to $2,000 and more. Handling Motor and Wiring Order Credits. In taking care of credit matters on orders for motors or for wiring the practice of the company is as follows : If applicant for motor or wiring is a consumer, both his service and mercantile accounts are scanned and if habit of pay is good the order is approved. If payment is slow or the customer's ac- count would not justify the amount or terms of the order, the customer is so notified and payment in full or in part, as the case may be, is requested in advance. Should the applicant not be a consumer, his rating, if any, is looked up, his references are investigated, and if found satisfac- tory the order is passed. If investigation proves otherwise, ap- plicant is notified and advance requested, and a copy of such notice is filed seven days ahead, which if not acted on, is removed from the file and a second or follow-up letter is written, a copy of which is also held seven days, at which time the contract is can- celed and returned to the contract department if the applicant's 230 CUTTING CENTRAL STATION COSTS check is not received. In some cases in the sale of motors, ex- haust fans, etc., chattel mortgages are requested to enable the company to recover property should the applicant default in pay- ment. COLLECTING THE ACCOUNT There are many ways of collecting accounts. Methods em- ployed by some companies irritate and antagonize customers. Other methods create respect. In some instances collection de- partments set out with the avowed intention of creating a reputa- tion for harshly handling customers in order that the customers' fear of such handling shall assist in reducing a number of over- due accounts. Some utilities have been known to go so far as intentionally to attract the attention of the delinquent's neigh- bors to the fact that trouble is ensuing over the payment of a bill. In general, however, this is not the accepted plan among more progressive central stations. Their plan generally is to adopt systematic, thorough and painstaking but withal firm measures of insisting upon payment. It is the endeavor to cultivate the good will of the customer rather than to antagonize him. Methods of a Middle West Company. As characteristic of these practices the following description of methods employed by the credit manager of a Middle Western electric lighting utility is of interest : This collection system requires the render- ing of three statements on all delinquent accounts, namely, the memorandum of arrears, the collector's statement and the ''Im- portant" statement. Formerly these statements were printed on addressographs from stencils used for printing the bills and were filled in by long-hand by statement clerks. Recently, how- ever, the department has adopted a very modern system of ren- dering these statements through the^use of four Underwood-type fanfold statement machines. The operation is now so handled that six copies are made in one operation, namely, memorandum of arrears, cashier's stub of memorandum, "Important" state- ment, cashier's stub of "Important" statement, collector's state- ment, office copy of collector's statement. When an account is ten days past due — that is, twenty days after the bill has been rendered — the company sends the customer by mail the memorandum of arrears, in which is printed the fol- lowing paragraph : METER READING, BILLING AND BILLS 231 "Please note that bills listed above have not been paid. As same are past due, the favor of your remittance by return mail is requested." This statement usually brings payment from customers who have misplaced or neglected their bills. To those who pay no attention to it, it is necessary to render the collector 's statement. This is sent out ten days after the memorandum of arrears state- ment was mailed. The collector 's statement is made in duplicate, one copy being for the collector and one for the office records. It constitutes the first call statement and is the beginning of the collection department's intimate relations with the customer. If the collector is not successful in securing the money on the first call, he leaves a collector's first notice, which shows the amount due and reads as follows : ''Your attention is called to your past due and unpaid account for electricity amounting to $ , covering dates for electrical merchandise $ , electric wiring $ . Please remit or call at our office and make payment without delay." Five days later, if no collection has been made, the "Impor- tant" statement is mailed. This bears a shut-off notice reading as follows : "We beg to draw your attention to your past-due account as listed above. We request that this account be paid before the close of business on . Otherwise we shall be obliged, w4th regret, to enforce our rule relative to discontinuing service. ' ' After allowing three days for the customer to make payment the collector makes his second call to collect or discontinue serv- ice. He must, however, interview the customer and get his re- fusal to pay before service is discontinued. In the event that the customer is not at home he will not shut off the service, but will leave a final shut-off notice which reads as follows : "We beg to advise that, in accordance with notice sent you for your unpaid account for electricity amounting to $ , call has been made to-day to shut off service. We hope you will ren- der this action unnecessary by paying bill at once at the main office." The Third and Last Call. This means that the third call must be made if the customer does not remit. On the third call the customer must pay or service will be discontinued. If conditions are such that the collector cannot reach the meter, the case is 232 CUTTING CENTRAL STATION COSTS turned over to the repair department to collect account or to discontinue service if necessary at the pole. Before this action is taken, however, a letter is addressed to the customer informing him that such action will be taken if the account is not paid. In the event that the service is shut off the collector leaves a slip at the meter showing the amount of the overdue account which was the cause of discontinuing service. Upon the payment of this account the customer can have the service reconnected the same day it is discontinued. As these various steps are taken memoranda are made on the customer's account at the office so that any inquiry as to the status of his account may be answered. After service has been discontinued for non-payment the re- port is held fifteen days, during which time another call is made to collect the account if possible. If the account is not paid, the contract department is informed of the situation and requested to issue an order to have the meter removed. Dealings with Customers Who Have Moved. The next task of the collection department is to get the money on the final ac- counts of customers who have moved or whose meters were re- moved on account of non-payment. First in order, there is the case of the customer who has moved and is using service at another address. If the balance owed is less than $1.50, the amount is added to his bill, which will be sent to the new address. If the amount is more than $1.50, it is given to a collector. If he does not secure the balance, he will leave a notice for the customer. If the customer then does not remit within ten days, another letter is sent requesting payment. Ten days later, if the account has not been paid, a shut-off notice letter is mailed stating that service will be discontinued within three days. Second, there is the case of the customer owing a final account who gave the company his new address at the time he ordered service discontinued but who is not using service at the new ad- dress. The collector calls upon this man and, if he cannot col- lect the amount, leaves a notice that the balance is due. If pay- ment is not made within ten days, two letters are written at inter- vals of ten days requesting payment. If remittance is not made then, the collector makes another call. If he is unable then to METER READING, BILLING AND BILLS 233 collect the amount or to get satisfactory promise of payment, credit data are referred to. If the correct business address of the customer is shown in the credit data, a call is made at this address and then a letter is sent to the business address stating that the account will be sent to an attorney for payment if it is not settled. After this a few more calls are made b}- the collector to establish definitely the fact that it is impossible to get the money. Then the account is turned over to the company's attorney with all of the collector's reports, copies of letters, credit data, etc. A card is also filed in the credit department's suspense file to prevent the delinquent from securing further service from the company while his account remains unpaid. Throughout all of these operations it is the intention of the department to exercise patience and to endeavor to cultivate the good will of the customer and at the same time to establish in the mind of the customer respect for the collection department. REDUCING THE DELINQUENT ACCOUNT BY 80 PER CENT. In one year the Muncie (Ind.) Electric Light Company re- duced its delinquency account from $12,591.98 to $2,225.51, or more than 80 per cent. This was done, says C. L. Walling in the Bulletin of the American Gas & Electric Company, the parent organization, first, by creating the office of manager of collec- Name Address _ Amount . Business . Remarlcs . Folio - J. E. No.. Date. Fig. 73 — FRO^fx of Card for Delinquent File 234 CUTTING CENTRAL STATION COSTS tions; second, by insisting upon a deposit with each contract; third, by never closing the books on a bad account, and, fourth, by keeping continually after the old offenders and educating them to pay their bills promptly. The following figures serve to show how well this plan worked out : 1917 1916 January $11,008.94 $7,444.22 February 10,348.00 9,064.80 March 6,839.73 9,672.39 April 6,703.13 9,461.24 May 5,513.07 10,302.97 June 5,140.99 11,038.65 July 5,123.06 12,278.54 August 5,144.66 10,441.52 September 5,017.13 10,393.71 October 4,510.52 12,350.35 November 4,913.11 15,597.56 December 2,225.51 12,591.98 A file of 3-in. by 5-in. (7.6-cm. by 12.7-cm.) alphabet cards (Fig. 73) is kept of accounts charged off as uncollectible, which LIGHT POWER MDSE. CASH Jan. ' Feb. Mar. Apr. May )un July AMg. Sept. Oft. Nov. Dec. Total I^G. 74— Back of Card for Delinquent Filf METEK READING, BILLING AND BILLS 235 furnishes quickly the following information : Name, address, amount, ledger folio, business, journal entry number, remarks. The reverse side is ruled so that an itemized account can be quickly entered (Fig. 74). During the year 1917 the company received many payments which are attributed to this card system. At the last of the month the new-business Ford is borrowed for a few days and a big drive on delinquents is made by the collection department. Delinquent letters are sent out as soon after the tenth as pos- sible to every delinquent account, and the delinquent list is kept up to the minute. NINETY PER CENT. COLLECTIONS BY TWENTIETH OF EACH MONTH Since the increase in postage the Indiana Raihvays & Light Company has been delivering the monthly bills to its 6000 INDIANA RAILWAYS & LIGHT CO. UGHT ANP POWER DEPARTMENT Office Houra! 7:30 a. m. to 5 p. m. Open Saturday* and lOth of Month until 8K)0 p. m. 1 12 E. Sycamore St. NoV. 30, 1917 Phone* 331-355 O Present Reading* La«t Reading* • . . K.W. H. Contumed. _perK.W.H.$. Let* Ic per ICW.H. on, until lOth. Net Bill for November Ls(* Unread Meter Minimum • • • . ) Light ( "°P"**] Appliance f ^■'"=« ' * - Total Amount Due J* All claims for adjustment mu»t be made by the fifth, -o All bills payable on or before the tenth. Positively no • > discounts allowed after that date. We have no collec- 3 J5 tors. Failure to receive bill does not eotitle the con- 3 sumer to exception to this rule. m November 30, 1917 Fig, 75 — Monthly Bill Form Used by Middle West Company 236 CUTTING CENTRAL STATION COSTS creditors in Kokomo on the first of the month by meter readers at a cost of approximately $35 per month, or, roughly, half a cent per bill. Bills are in card form, see Fig. 75, the cards measuring 3^/4 in. by 5^/^ in. (8.25 cm. by 14 cm.). The back of the card is used for timely advertisements. A discount of 1 cent per kilowatt-hour is allowed for payment before the tenth, and it is noticed that approximately 80 per cent of accounts take ad- vantage of this. On the twentieth delinquency notices. Fig. 76, are mailed. Only one such notice is sent out by the company to a delinquent. Collections are as follows : Eighty per cent by tenth of month Form 215. 2in 12-17 INDIANA RAILWAYS AND [I! UGHT COMPANY KOKOMO, INDIANA Light and Power Department No.. -191 M- As the bill presented for electricity , 191 . , amounting to $ may have been lost in transit, mislaid or perhaps forgotten, we take the liberty of reminding you that the ten- day limit will expire ■ 191 , at 12 o'clock, noon, after which date service will be discontinued without further notice. A charge of $1.00 is made for re-connecting. Respectfully, INDIANA RAILWAYS AND LIGHT CO. Our consumert will »ave at least one month's lighting bill in the course of a year if they will take ad- vantage of the discounts given by paying on or before the last day of the discount period. Fig. 76 — Delinquency Notice Mailed to Tardy Customers following period energy was used; additional 10 per cent by twentieth of same month ; additional 9 per cent by twentieth of following month — leaving approximately 1 per cent for discon- nection delinquents. As will be noticed, a charge is made by the company of $1.00 for re-connecting service after disconnection or for failure to pay in the proper time. METER READING, BILLING AND BILLS 237 METHOD USED TO DECREASE DELINQUENT ACCOUNTS Among the plans which are being developed to assist in hasten- ing customers' collections, those which are based on the reconnec- tion charge idea are said to be most effective. The accompanying form shows how this idea is applied by the Indiana General Service Company of Muncie. With this company all bills are due on the tenth of the month. After the tenth all delinquent INDIANA GENERAL SERVICE CO.- t)«te According to our records your ircoant showi t balance of t «hleKd froui lime lo time (or wliidi jcrvice I »%\tf to piy monthly at yonr Office at the following Rate Snbject to a minimum monthly ptymeot o( j^,"- dollars ($ , Meter rent per month. Subject to a discount for prompt pa>nieiit o( 1 i( paid wiihin discount period. ' % This agreement to be effective for one year from above date and to continue in effect thereafter nntil notice in wrilinR of 30 day» shall be given for the discounef lion of the service. WilHttt Applicant 'the forgoing is sfgned by the applicant after reading and receiving a copy of same, and is flil'ject lo rtie Company's accrptaitre by letter addressed lo con>umcrs wilhiii thirty days acceptance may aho be nude by making connection al llie point of delivery. RrCfived from the snin of dollars (S ) or Inter nf security No as Rii»ri>rii-e for Hie fnlfilmenl of above applicatiin Jicli giiarmitee to be returned »btn the >ervice roiercrt by ilii> appliciition isdisconiinnid Householder ? ■ Id Ih SMIIIIII CIIIOI roaii (< |.< Fig. 80 — Card Contract Used by Montreal Company 254 CUTTING CENTRAL STATION COSTS The average contract used by light and power companies is crowded with numerous regulations legally phrased and which not infrequently serve to frighten the prospective customer, especially if he be a householder. In addition, as has frequently been shown, such contracts do not lend themselves readily to con- venient filing. With this Canadian company the regulations are kept on file and are available whenever required, while the card, satisfying all practical purposes, is filed with others of its kind. The card when filed constitutes an option on the customer's business for a period of thirty days. Besides, it acts as a deposit form. A copy is retained by the customer. APPLIANCE SALES COMMISSION FUND FOR THE SALESPEOPLE To give an added impulse to appliance sales in 1918, the Poto- mac Electric Power Company of Washington, D. C, placed aside a 5 per cent commission on everything sold out of the electric shop which is paid into a monthly fund and distributed to the members of the sales department. This distribution is made by equal division ; that is, if the profit for the month is $250 and there are ten salesmen on the staff, each one receives a check for $25. It is found that this is aiding materially in the develop- ment of an organization spirit because of which the men are co- operating eagerly and "tipping each other off" to opportunities discovered outside the discoverer's own territory. INSTALLMENT PERIOD ON RANGE CUT The plan under which the Pacific Gas & Electric Company of San Francisco formerly sold electric ranges called for 10 per cent cash and the remainder in twelve monthly payments. The com- pany paid the installation cost, which was figured to amount to $50, and this amount was allowed on all ranges installed on the company's lines whether sold by the company or by outside agen- cies. If the customer desired to pay cash for the range, a dis- count of 10 per cent was allowed. Since the power situation in California has grown acute through the increase in the price of oil, abnormally low stored water supply and rapidly increasing demand for power, the COMMERCIAL DEPARTMENT 255 range policy has been revised so that it will no longer be a bur- den to the commercial department. The present plan is to sell at manufacturers' list less $20 per range, which is deducted as an allowance on cost of connection ; the average installation cost is about $50, or $60 including water heater. The terms of pay- ment are 25 per cent cash and the remainder in three monthly payments. If the customer desires to pay cash, a 5 per cent discount is allowed. The connection allowance of $20 is made only if the range is sold by the company. The rates remain the same as before (averaging slightly less than 4 cents per kilowatt-hour), and the same service to con- sumers will be continued. Under the new plan the cost to the consumer will be greater, but it is hoped that the electric range department will be self-sustaining. PEAK-LOAD RELIEF Equalization of the peak loads of customers in order that existing station capacity can be utilized more fully is of unusual importance at the present time. At the 1918 N. E. L. A. con- vention at Atlantic City, N. J., R. R. Young presented a paper telling how this plan was worked out and of the results obtained by the Public Service Electric Company of New Jersey. The territory of this company in so far as generation and dis- tribution is concerned is divided into two zones, designated as northern and southern zones, the southern zone comprising Tren- ton, Burlington and Camden with adjacent territory, the north- Results of Campaign to Equalize Customers' Peak Load Total K\v. Connected Load in Division Power Essex 73,000 Hudson 40,000 Passaic 20,000 Central 41,500 Bergen 9,700 Total 184,200 Southern Zone . . 23,900 Promised Promised Per- Actual Relief Kw. centage Obtained Relief Relief Kw. Percentage 4,360 5.9 5,245 13.1 1,852 9.2 3,909 9.4 1,050 10.8 8.9 16,416 10,000 5.4 2,931 12.2 1,500 6.3 Grand total 208,100 19,347 9.3 11,500 5.5 256 CUTTING CENTRAL STATION COSTS ern zone comprising all north of and including New Brunswick and its adjacent territory. Late in the summer of 1917 the company found that it would be unable to start a 35,000-kw. turbine and a 12,5()0-kw. turbine which were under erection in two of the largest generating sta- tions. It was decided, therefore, that, beginning with November, ESTIMATED MAXIMUM FOR 1917:., •1 ^1^0 / ^ c / r *^^ ^^^ k if) D O J r N £ 100 / / y — f o y s^ / r ^ 50 y / ^ K-- SE PJ- -H <— -0< :t.- .-> U- -NO v.- --> k-- DE c.-- — -> ESTIMATED MAXIMUM FOR 1917 .. % 24 D O X t- •^ 20 o o ^ re f ,/ s. /I > V / , / \ y s^ / V -«-. s_ ^ V. / V / 4 / / U- SE =T:- -->■ .... ■oc -T." — >l k- ■NC )V- ..^ k- ■DI ic- ---> Fig. 81 — Peak-Load Distribution of New Jersey Electric Company; Northern Zone Above, Southern Zone Below a systematic canvass of power customers should be made, asking the co-operation of the manufacturers using 50 hp. and more in redistributing their load throughout the day so that heavy de- mands which ordinarily might occur between the hours of 4.30 P. M. and 9 p. m. would be changed to some other hour during the twenty-four-hour day. COMMERCIAL DEPARTMENT 257 Blueprints showing a typical twenty-four-liour composite load curve of the generating stations for December, 1916, were pre- REPORT ON REDUCTION OF PEAK Customer Business Address Town Substation from which customer is fed Connected load hp kw. Maximum demand kw. Demand 4 to 9 p.m kw. Promised relief at peak kw. Remarks: Interviewed by: Signed : pared for the power representatives and agents, and a mock inter- view was held to illustrate the methods to be used in presenting the case to the manufacturers. After the compam^'s organization had been thoroughly pre- pared, the men began about Nov. 1 to visit the power customers, the campaign continuing throughout the month of November. Report forms were prepared (Fig. 82) and results of calls on individual customers were reported daily, these reports being tabulated by the general office. Weekly meetings of the power representatives in the state were held to discuss difficulties en- countered and methods of overcoming objections. Inasmuch as the rate schedule includes no off-peak provisions, the only advantage the manufacturer was to derive was the possible reduction of his average demand, thus reducing his demand charge somewhat, besides giving him greater insurance against interruptions in service. The result of this campaign in promises from the customers is shown in the table. Owing to the fact that customers were probably not able fully to live up to their promises, and there being some diversity in the peak loads, it is estimated that the result of the off-peak canvass was the securing of approximately 10,000 kw. reduction in demand in the northern zone and 1500 kw. reduction in de- 258 CUTTING CENTRAL STATION COSTS REPORT ON REDUCTION OF PEAK Customer Business ■. Address Town Substation from which customer is fed. Connected load hp kw. Maximum demand kw Demand 4 to 9 p.m kw Promised relief at peak kw. Remarks; Interviewed by: Signed: Fig. 82 — Report Forms for Calls on Customers mand in the southern zone. In fact, the maximum peak occurred in the last week in November in the northern zone, whereas, the peak of former years had been occurring in De- cember. Kilowatt-hours sold during November and December indicated that no curtailment of use resulted from reduction of peak. In other words, the maximum capacity required was reduced by 11,500 kw. without reduction in output on the part of the manu- facturer. The daylight-saving law as now effective will not help the fall peak. If the period is extended to cover the entire year, the saving in necessary capacity by the central station will be con- siderable. COMMERCIAL DEPARTMENT 259 FINANCING NEW TIE LINES Under present conditions, witli coal at a high level of prices and with winter-time deliveries of fuel very uncertain, many a company operating a small steam plant naturally feels that it would like to tie in with a neighboring large transmission com- pany if possible. By so doing it not only shifts the generating responsibility to another company which may have some water power, but it also may reduce somewhat its production cost and put off into the far future any possibility of expenditures for plant replacements. From the small plant's viewpoint intercon- nection at the present time has many advantages. When the tentative proposal to the transmission company is made, however, the difficulty of financing the tie line between the present transmission system and the small steam plant looms large. The large company is having trouble taking care of the financing of necessary war business and its own community. The transmission company would be glad to furnish the service at 2.5 cents to 3 cents per kilowatt-hour, however, if the financial difficulty were not in the way. In the Northwest a number of companies are getting around their troubles in a common-sense sort of way. The small com- pany with the steam plant is financing the line and in turn is selling it to the transmission company, taking in payment the stock of the transmission company. This plan works well for several reasons. First, the small company can easily raise the money for the line in its own little community because its present security holders and the other investors in its town are in busi- nesses that are not greatly affected by war. They are accus- tomed to putting their income in banks or putting it back into their local business and are willing to divert it to a local utility enterprise at a fair price. So the small company can raise the money. Second, it appears a good stroke of business to take the large company 's stock in payment for the line because they get it at a price to yield around 8 per cent and are likely to come out handsomely on any advance in market value. This method is satisfactory to the large company particularly because it relieves it from the financial strain. It is usual practice for the small company to draw the specifications for the line it expects to build and then submit them to the engineers of the larger company for 260 CUTTING CENTRAL STATION COSTS such revision as may be thought necessary to make them conform fairly well with the transmission company's standards of con- struction. The small company then does the actual building of the line. This has been found wise under present circumstances, for the small company can usually build the line at a great deal lower cost than the transmission company. At first it may seem paradoxical that the small company with less experience can build cheaper than a large concern with transmission specialists. It is true nevertheless. The difference in cost comes largely in the labor-camp and transportation expense. The small company can pick up labor in its own easy market and usually makes no special provision for housing and feeding the men. They know the community and shift for themselves. Farmers with teams do the hauling during lulls in farm work, and this keeps down transportation expense. This plan of providing service has, therefore, many advantages to both companies. It is being used to the mutual advantage of concerns in the Middle West and Northwest and is at the same time making for increased capacity in the small towns and for conservation of the nation 's fuel. METHODS OF FINANCING EXTENSIONS OF LINES Before a recent meeting of the commercial men of the Indiana Electric Light Association, R. Thurman of Muncie presented a comprehensive digest of plans used by various utility companies in the Central West for financing extensions under the present conditions. Owing to the high cost of materials and labor and to the fact that utilities probably will not be allowed to capitalize at this high figure, only absolutely essential additions will be made, Mr. Thurman pointed out. As to what is considered essential, this will vary with each utility and with every case presented. How- ever, there are in most cases different ways of taking care of lighting and power customers. A brief summary of a few of the different systems follows. In the standards of electrical service established by the Public Service Commission of Indiana, dated Jan. 2, 1918, Rule 31 pro- vides that each utility shall, upon request for service, make free of charge any line extension necessary to give this service, when COMMERCIAL DEPARTMENT 261 the income for the first year from the prospective customer is equal to one-half the direct cost of the extension. If the cost of the extension is greater than the estimated income for the year, the customer is required to deposit the cost of the extension above the free limit. If other customers are taken on this extension, the original consumer is to receive a rebate of an amount equiva- lent to the cost of the free extension for each customer so taken. A number of companies are using this rule with reference to both light and power, particularly lighting consumers. In figur- ing the cost of the extension, the majority of utilities include the cost of material, cost of labor, including meter and meter installation, and to this add 10 per cent to cover cost of engineer- ing and superintendence. The Pacific Light & Power Company of Portland, Ore., uses the same method as given in Rule 31 (see Electrical World, Feb. 9, 1918, page 311). Some companies are requiring the total amount of the cost of extension to be advanced by the consumer, especially the power consumers. This is returned to the customer in energy, in some cases the total amount of the bill being applied each month, in other cases from 25 per cent to 60 per cent of the bill. Other companies use a plan in which the total cost is advanced and an amount equivalent to the 1914 cost is returned in service. This applies in the majority of cases to large extensions for additional power consumers. This seems to the author to be a very good method of taking care of high-cost extensions, owing to the fact that it is probable the utility will not be allowed to capitalize the full amount expended on these extensions. One company at the present time is asking that the total cost be advanced and promises to return nothing. This applies only to lighting consumers. In this connection the question of how an extension made in this way can be capitalized arises. An- other plan is to set a limit for cost and then to ask the customer to pay any additional expenditures. This plan applies particu- larly to lighting consumers, and the amount set as a limit to be spent for each lighting customer varies from $20 to $50. The consumer is required to deposit in most cases any additional amount, which is returned to him in energy. Under the terms of still another system the prospective consumer is required to purchase preferred stock to the amount of the cost of the exten- 262 CUTTING CENTRAL STATION COSTS sion. In most cases this preferred stock pays a dividend of 6 per cent, which really amounts to borrowing the money from the consumer at that rate. This seems to the author to be one of the very best methods of taking care of extensions at the present time, owing to the fact that it not only secures the necessary cap- ital but also gives the customer an interest in the company. In securing data for this paper a circular letter was sent to each of the central-station members of the Indiana Electric Light Association asking for information regarding their method of taking care of extensions. Answers from seventeen central stations were received, which are classified as follows: For Lighting Customers: Xo extensions being made 5 Xo advance required 5 Extensions made according to commission Rule 31 3 Total amount advanced by customer, nothing returned 1 Customer required to buy preferred stock equivalent to cost of ex- tension 1 For Power Extexsioxs: No extensions being made 5 No advance required 4 Advance required, but total amount returned in energ;^'^ 5 Customers required to buy preferred stock equivalent to cost of ex- tension 1 A number of the replies from central-station companies, especially the smaller ones, revealed the fact that they were hav- ing trouble with their customers in securing necessary cash to finance extensions. In some cases this had assumed such pro- portions that it was necessary absolutely to call off plans for ex- tensions of any kind, on account of prospective customers refus- ing to advance the money by any of the above methods. This, however, the author believed is because the applicants for service had not been educated up to a point where they understood that it was impossible at this time for a utility company to make an investment in anv other wav. FINANCING THE FARMERS' LINE Running north from Berrien Springs, Mich., through a rather thickly settled farming community, is a newly built 9-mile (14-km.) extension to the system of the Indiana & Michigan Electric Company of South Bend, Ind. The line serves farmers ... COMMERCIAL DEPARTMENT 263 only. It operates at 4400 volts, single-phase, and is constructed of 30-ft. (9-m.) wooden poles spaced on 150-ft. (45.7-m.) centers and carrying No. 6 copper wire. The line cost $11,800 and reaches 120 customers. To finance the line each farmer gave the company his promissory note for $102 before construction was started, with the understanding that the entire amount should be refunded in electrical energy at the rate of $1.50 per month. In all the company collected from the farmers $12,240, which it will have returned at this rate in about five and one-half years. The average customer on this line has a ten-room house, each room of which is wired for electric light. The average cost of wiring and fixtures complete, ready to turn on the energy, was $70 for a ten-room house. The average connected load in a ten- room house on this line is 600 watts. In connection with this lighting load there will be more than fifty motors of 1 hp. or less, which will be used for pumping purposes. In such cases where the motor rating does not exceed 1 hp. in capacity it is attached to the regular lighting meter and adds nothing to the monthly minimum charge. There will also be a number of motor connec- tions for units of larger capacity than 1 hp., and in such cases the motor will be put on 220 volts and a service charge of $1 per horsepower per month will be added to the energy charge. Prac- tically every farmer along the line has signified his intention of wiring his barn and garage, so the total lighting load will soon amount to about 700 watts per customer exclusive of the motors. The 120 customers will be served from thirty-five transformers, in some instances as many as five customers being served from one transformer. It is interesting in this connection to know that where a farmer has a tenant house on his farm he can make connection to this building without extra cost to him except the cost of wiring the building. The lighting rates charged on this installation are 11 cents per kilowatt-hour, with 1 cent discount, making 10 cents net with a $1.50 minimum charge per month. The average income for rural lines for residential lighting is approximately $150 per month, making an income on this line of approximately $2,160. When all appliances and stoves are on, as they will be within one year, the gross income will be approximately $3,500, which is approximately 30 per cent of the cost of the line. This, it is figured, will give the company the income it requires on the line. 264 CUTTING CENTRAL STATION COSTS These rates and this financing plan do not include any provision for the long drop necessary to reach some farmhouses far back from the road. In the construction of the line the company allowed 300 ft. (91 m.) for each service connection. In case the customer's house was more than 300 ft. from the line, he was required to pay for all additional construction at the rate of $25 per 150-ft. span. The amount paid for this additional con- struction is considered as payment for a private line which is owned by the customer but maintained by the company. The company's viewpoint on the situation, as explained by M. F. Caldwell, manager of the new-business department, is given in the following paragraphs : ''In serving the farmer life is made more pleasant for him, since electricity lessens his desire to go to the city in order that he may enjoy the city's luxuries. If the central station can meet these demands of the farmer, more food will be raised, and it takes food as well as bullets to win the war. Moreover, after the war there is likely to be a period of readjustment in some of the country's industries that will cause a reduction in demand by some of the central station 's power customers. With the farmer it is hardly expected that there will be such a period. The line which is built now will be paid for while the farmer is receiving top price for his goods and while it is easy to sell him electric service. Therefore, why not meet his demands now while he has the money and is willing to spend it? If he does not spend it for these improvements, he will spend it for something else which will perhaps do him less good, and the central station will lose an opportunity to get his business and to keep him satisfied on his farm raising food for the nation. ''In cases where a careful survey shows that the line would give insufficient revenue to pay a reasonable profit on the invest- ment, the company believes that sufficient of the farmer 's deposit should be retained to reduce the investment to a figure which the revenue from the line will justify." CUSTOMERS TO PAY EXCESS OVER 1914 COST A new system of service charges has been adopted by the Alliance (Ohio) Gas & Power Company, effective Nov. 1, for residences and commercial loads of 5-kw. rating and less. This COMMERCIAL DEPARTMENT 265 applies in any instance where tlie company is required to make an expenditure (1) for the installation or construction of ad- ditional or specific overhead lines on streets, alleys, highways, rear lot and side lot lines, including poles when necessary, and usual equipment, wire, lightning arresters, line switches, ground wires or connections, or for any work on existing polos wnth all of the attendant equipment for increasing the existing distribu- tion system or transmitting direct to the applicant's premises; (2) for transformers wherever installed, excepting only standard service transformers, and (3) for construction on applicants' premises exclusive of overhead service loops, meter and anj^ over- head or underground construction on rear or side lot lines as already described. The applicant is required to deposit with the company an amount equal to the estimated cost of the w^ork done upon the understanding that the work constructed shall remain the prop- erty of the company. However, a refund to the amount of the estimated cost of this work, except construction on applicants' premises, as of July, 1914 (called normal cost), will be made to the depositor at the rate of $20 for each customer's installation connected to this work within ten years. This refund shall not exceed the amount of the normal cost and shall not be payable unless written notice is given by the applicant to the company of the consumers ' installations connected to this work. No inter- est is allowed on the amount deposited. Furthermore, the com- pany has the right to refund at any time all or any part of the unrefunded portion of the normal cost of the work. Moreover, each additional customer on this line connected within ten 3'ears of original contract date shall pay one-tenth of the cost of this construction above the normal cost at the time of filing his application for service, which amount shall be re- funded to the original depositor until nine-tenths of this abnor- mal cost shall have been refunded, when such collections from applicants and refunds to depositors shall cease. The Alliance company is a Doherty property, and it was stated that other Doherty properties in Ohio would probably follow this method, which has received the approval of the Ohio Public Utilities Commission. 266 CUTTING CENTRAL STATION COSTS FIXED PRICE ON SHORT EXTENSIONS The problem of line extensions during war times has in most instances been solved where long extensions were to be made. Short extensions, merely connecting a service on existing line, also require capital, and the expense involved may easily run into a good many hundreds of dollars in a short time. The Elmira (N. Y.) Water, Light & Railroad Company has found a way of obtaining the required money by applying a customer-financing method to even the small extensions. Each prospective customer is approached frankly and told of the conditions faced by the utility in war times and of the neces- sity for having financial assistance wherever extensions are re- quired. It is pointed out that utilities must refrain from issuing securities at the present time unless authorized to make an issue and that consequently funds are not available for line extensions. It is further shown that the increased costs of labor, materials, fuel, etc., have reduced the net income to such an extent that financial assistance must be had from prospective customers. However, the customer does not pay for the line but only lends the necessary money at 6 per cent for such time as the company needs it. The company guarantees to recall all of the outstand- ing certificates that it has issued and refund the total amount of the money that has been advanced with interest added. Care has been taken to impress upon all customers this fact that they are not buying or paying for the service, but are merely assisting the company in financing the purchase of the necessary material and labor. The company does not refuse to run any extensions, but points out to the customer that unless financial assistance is ren- dered the company will not be able to make the extension until some other way has been found to finance the proposition. Where it is necessary to extend the wires a distance of 300 ft. to 500 ft. the company first finds out from the line department what the cost of these extensions will be. On ordinary service, however, where the secondaries run right up to the house the company has been asking the consumer to advance $11. This has been found to be about the average cost of service during the months of June and July. Prior to that time the cost was a trifle less, the increase being due to the gradual advance in the cost of material and labor. COMMERCIAL DEPARTMENT 267 Should a prospective customer point out that it is impossible for him to advance the cost of the extension, he is then asked to go to the bank and borrow the money, and this has been done in some instances. The Elmira company was wiring about 100 houses a month during 1918, and in each instance the customer was asked to ELMIRA Water, Light & Railroad Company Elmira. N.Y. ADDUM AU. ooMmnncAii 1518. Bear Sir:> Wi ackaortede* «lth thsma, roc«lp» of yoor deposit of $ to \>» «5iplio4 on account ef the cost of coo- •tniction of extension to your property sltoated »t As soon u ruisccial conditions poxBlt of our BWltetinB secaritles at fcrorabla prices, w v.ill »ajce xjp tlw natter of our flnacclw: this construction. Md in tt» ovont of our anility to do »o. tho oathod to »o adopted u roolttiac to jon tho amount deposited <7ith us. U> the ncifltUM. tbla letter wU servo as a receipt for your payncnt ui orldenee Appr«cl.-tl;« your cooporotlon, ne ara ResTectfMlly yours, Ojncrsl Manager. llBjra tteter. Light i Billroad CccfiDJ. , Fig. 83 — Certificate of Receipt for Money Advanced by Customer assist in the service construction. Almost always he has ad- vanced the money. It was also found necessary to impress upon all employees the necessity for taking this step so that they can speak intelli- gently on the subject to any one. In addition, each of the elec- trical contractors in the city and surrounding counties has been notified what the company is doing so that no consumer will have his house wired without being absolutely familiar with the con- ditions of connection to the company's mains or secondaries. SERVICE-CHARGE FOR POWER LOADS A new customer's charge for commercial loads in excess of 5 kw. capacity has been drawn up by the Alliance (Ohio) Gas & 268 CUTTING CENTRAL STATION COSTS Power Company, effective Nov. 1. This applies in any instance where the company is required to make an expenditure (1) for the installation or construction of switching apparatus, for ad- ditional or specific switchgear, meters, instruments, panels, frames, control, cables and buses, connections and transformers, in switch houses or substations; (2) for additional or specific overhead lines, including poles or towers, with necessary and usual equipment, wire, lightning arresters, line switches, ground wires or connections, or for any work on existing poles or towers, with all the attendant equipment for increasing the distribution system or transmitting direct to the consumers' premises ; (3) for any transformers installed in switch houses, substations, line houses or other structures not otherwise specified, and (4) for service on customers' premises, for the installation of poles, power lines, ducts, cables, and also where the transformer capacity to be installed exceeds 50 kw. for the transformers and switching required and for special transformers of 50 kw. rating or less. The company contracts to supply a given amount of kilowatt line capacity to the premises in question, and this capacity the company agrees to hold and reserve for use of the applicant ten years from the commencing of supply, subject to federal, state, county, township or municipal regulation. How the Refund Is Worked Out. A deposit of the esti- mated cost of the work upon the understanding that the work shall be the property of the company is required. A refund will be made of the estimated cost of this work as of July 1, 1914 (called the normal cost), (A) on the energy used by the applicant and taken from the line constructed as specified, and (B) in addition on the energy taken and used by other consumers con- nected to the lines so constructed, except where the work con- structed consists of feeders or an addition to the network, in the general distribution system of the company, in which event refund to the applicant will be made only on the energy used by those consumers who are connected to that part of the work specifically constructed for the applicant which extends beyond the network of the general distribution system of the company. Provision is made, however, that in no case shall the amount refunded to the applicant on the energy used by any consumer exceed the normal cost of that portion of the work constructed COMMERCIAL DEPARTMENT 269 which is useful in serving that customer. That amount refunded to the applicant should be based upon the energy taken and used within ten years after commencement of supply, and the total amount of the refund should not exceed the normal cost of the work applied for. Moreover, the refund will be computed at a rate per unit as determined by the following formula : Refund rate per kilowatt- hour = dollars -f- (36,000 X contracted kilowatt demand). The sum of the money in this formula is the normal cost of the work as described. The refund will be paid by the company to the applicant annually. The kilowatt demand in this formula is the capacity contracted for and reserved to the use of the applicant by the company. No refund or interest shall be paid unless the applicant's bills for energy have been paid in full, nor shall any annual refund payment exceed 50 per cent of the sum of the bill for the energy used within the refund period from the work of construction under the application. Besides, the company reserves the right to refund at any time all or any part of the unrefunded portion of the normal cost of the specified work. No refund of interest whatsoever will be allowed on the excess cost of the specified work, which excess is the difference between the normal cost and the amount deposited. Interest not exceeding 6 per cent per annum will be paid by the company to the applicant annually upon the balance of the nor- mal cost held at the time and subject to be refunded, and this annual rate of interest will be computed by this formula : Rate = 0.6 of 1 per cent X average hours' use per daj^ of the contracted kilowatt demand. The hours' use per day of the contracted kilowatt demand in this formula is to be determined by dividing the monthly aver- age of kilowatt-hours upon which refund is allowed by thirty times the demand contracted for. PAYING DEMAND-METER INSTALLATION EXPENSE When a Middle Western central station began to install de- mand meters on its larger industrial customers' installations it found quite frequently that services were taken into the premises from two or more widely separate points. To rearrange the 270 CUTTING CENTRAL STATION COSTS wiring so that the total instantaneous demand could be measured on a single meter meant a considerable expenditure. The com- pany did not feel that it could afford to go to the expense of making the change. At the same time it realized how much to the benefit of the customer it would be if the change were made. To induce the customer to pay for the change in this wiring, therefore, was the problem. In most cases the difficulty was cleared up by measuring the demands on the separate services and presenting a bill based on the total of the separate readings, together with an explanation of the reduction which could be made if the owner would change his wiring so that the demand could be measured at a single point to give him the advantage of his load diversity. SECTION VI MANAGEMENT SELLING STOCK LOCALLY A STOCK-SELLING Campaign in its home territory just completed by the Dayton (Ohio) Power & Light Company was somewhat unusual in that it was handled by the company's own men exclu- sively. The major portion of the work was carried b}^ the com- mercial department under the direction of Thomas F. Kelly, An Investment Opportunity In One of Your Public Utility Properties Ao opportunity is nojr available to our cutomert to beoome finkncially inter- (•tad ia this large public titility system — to share io the moderate returns follow- ing efficient, progressive and economical management and full consideration for the rights of the public. The Dayton Power & Light Company is now operating in Montgomery, Qreene, Clark, ClintOD and Miami counties and supplying electric aerrice in forty-one coDimunities including the cities of Day- ton, Piqua, Xenia and 'Wilmiiigton. lu addition we supply Steam Service in Day> ton, Heating Service in Piqua and own and operate the Waterworks system of Wilmington. We desire to encourage increasing proprietorship in the company by all cus- tomers. There are at present more 'hau 1200 widely-scattered stockholders. Amons th« many reasons commending the purchase of the 6% Cumulative Preferred Stock of the Dayton Power & Liaht Company now ate the following: We will seU a $100.00 share for $83.00 in cash or in monthly payments and you will earn 7% on your investment. Each share can be purchased by pay- ing $10.00 down and the balance in five pajTnents of $15.00 each. Dniinesa and gross earnings have steadily and substantially incrensed since organization in 1911. This stock has paid quarterly dividends of 6% per annum regularly since the or- gioizstion of the company. The company is a' large organization with annual gross earnings in excess of $2,000,000 and with properties located in diversified communities. The company publishes an annual re- port which is tccompanicd by corlilicatc of audit by an independent auditor. Dividends on three or more shares ivill return to you enough to. pay the average residential light bill for a year. Your capital and the money it.200 Volt Source of Enerqy Distribution |Transforrrier Kim r'^^^mm^m^ Secondary Ltads open Lighting Transformer Fig. 88 — How Auto-Transformer May Help Power Factor with lower voltage units. To improve conditions a distribution transformer was connected across the source of supply as shown in the accompanying diagram, Fig. 88. Its primary acted as an auto-transformer and its secondary was open. The primary was 284 CUTTING CENTRAL STATION COSTS tapped midway between the two terminals, 1100 volts being im- pressed upon the terminals of the lighting transformer. This greatly increased the power factor of the system and obviated the purchase 'of an additional step-up transformer of correct size. Of course, this connection was facilitated by the fact that the distribution transformer had 50 per cent taps on the primary. IDLE GENERATOR IMPROVES POWER FACTOR It is not unusual to connect a synchronous machine to some part of a circuit to improve the power factor, but a company in New England has found a method of doing this which utilizes any generators which may be idle. This is made possible by the fact that it has duplicate transmission lines running from its main generating station, only one of which is ordinarily required to carry the load. The other circuit is provided for emergency use and also to take care of future increases in load. When the power factor gets low the duplicate lines are paralleled at their distant ends, and any generator that may not be carrying load is connected to the reserve line. It is then allowed to run as a synchronous motor, being excited enough to compensate for the low power factor at the delivery end of the line. A slight load can be put on the generator if necessary to secure the desired wattless current by allowing some water to flow through the waterwheel. This arrangement, besides utilizing equipment that would otherwise be idle, improves the power factor in both the line and the generators carrying load, whereas if it was merely floated on the bus as a synchronous condenser it would not benefit the line. By so doing it is also possible during a sleet storm to circulate enough current through the reserve line to melt any sleet which may adhere to the conductors. CORRECTING POWER FACTOR IN DISTRIBUTION CIRCUIT To take on an additional load of 160 hp. in a 550-volt secondary network system, where the primary feeder, switchboard panel and transformers were operating at over capacity, 570 kva., at a power factor averaging 60 per cent and at times running as low MANAGEMENT 285 as 50 per cent, was the problem which confronted the engineers of Lynn (^lass.) Gas & Electric Company about three years ago, according to J. F. Dubois, manager of the electric department. The company was supplying energy to the neighborhood contain- ing the factory by a 550-volt secondary network, shown in Fig. 89 in single-line diagram, banks of transformers lieiug connected in at various points. Two courses appeared open — first, to improve the power factor of the operating circuit, and second, to install a new circuit with the necessary transformers, etc. The matter was discussed with engineers of the General Electric Company, who suggested that static condensers might be utilized, although no equipment of this kind for outdoor w'ork had been developed at that time. It ap- peared that if the second plan of dividing the existing network and installing the necessary transformer and three-conductor cable from the station, together with switchboard panel and in- struments, was followed, the operating conditions would not be improved, but that existing troubles would be increased. The generators would still be supplying the cables and transformers, with the transmission of a large wattless current. On the other hand, by the use of the static condenser the overload on the cables Fig. 89 — Location of Transformer Banks and Condensers would be reduced. Generator and transformer capacity would be released for other service and the power factor would be im- proved along the whole system back to the generator. No ex- 286 CUTTING CENTRAL STATION COSTS citation or operating labor would be required for this form of apparatus. Early in 1915 two static condensers rated at 100 kva. each were installed and connected to the secondary network. Space not being available at the factory first mentioned, one unit of Reactance X. u jTiG. 90 — Arrangement of Static Condenser Equipment Stations 100 kva. was located in a machine shop across the street. At another point, between banks of transformers shown in the circles in Fig. 89, a portable galvanized-iron building was erected to house the other condenser. The company found it- self able to take on this factory of 160 hp. in motors without the addition of a single transformer or the changing of the circuit in any way except in the installation of the condensers. The power factor of the circuit at the station was raised to about 78 per cent. The results from this were so satisfactory that in the past year another unit, of the subway type, was installed in an or- MANAGEMENT 287 dinary transformer manhole on ]\Iunroe Street, Lynn. In this case the cells are inclosed in two tanks, the accompanying reac- tance being inclosed in a smaller tank about the size of a 5-kva. transformer. An oil switch and contactor are inclosed in an- other tank, and an ammeter with transfer phase switch and push- button control are placed in a pedestal on the sidewalk. This equipment is working perfectly at present and in a recent test it raised the power factor of the circuit at the station from 60 per cent with the condensers all off to 90 per cent with all the units in, the present load being about 440 kva. IMPROVING POWER FACTOR AND VOLTAGE REGULATION Since early in the summer of 1917, writes J. T. Peyton, of Westinghouse Electric & ^Manufacturing Company, the Duquesne Light Company, serving the Pittsburgh district and the counties of Allegheny and Beaver in the southwestern part of Pennsyl- vania, has had in operation on its lines a 7500-kva., 11,000-volt, 600-r.p.m. synchronous condenser for raising the power factor of the system and maintaining voltage regulation. After this con- denser was put in service and its ability to handle the unfavorable conditions imposed on the Rankin plant was successfully demon- strated, the Duquesne Light Company ordered two duplicate machines. One of these was installed during April at the Beaver Falls substation, 32 miles (51.5 km.) from the Brunot's Island plant, and connected by two 66,000-volt transmission lines, each having a capacity of 20,000 kva. This station is at the end of the 66,000-volt system, and the load at that point at the present time is only about 500 kva., so the condenser for the present Avill be used for controlling the voltage, some method of regulation being necessary on account of the line impedance and the comparatively high reactance of the transformers now in use. The other one, when completed, will be placed in the Lawrenceville substation, where the conditions are somewhat similar. As the company ex- pands and the load on the system increases, it will very likely continue to place synchronous condensers at the principal load centers, and the time may come when it can obtain practically a flat voltage curve notwithstanding variations in the power factor. Benefits of Synchronous Condensers. There is nothing new 288 CUTTING CENTRAL STATION COSTS in the application of synchronous condensers to this class of service, for there are many of them in operation to-day and have been for years. However, when one stops to consider that many of the companies are operating close to maximum rating during these war times, and that generating equipment is necessarily at a premium with a large number of them, it is rather surprising that these machines are not in greater demand. In all proba- bility there are many cases to-day where the conditions are such that the introduction of a condenser would solve the problem, or at least go a long way toward the solution. With the unprece- dented increase in prices of apparatus and materials of all kinds, the vital consideration, of course, is the expense incident to any change involving new equipment or construction work. How- ever, a little analysis on the part of the operator who is pressed for sufficient capacity may reveal the fact that by the use of a synchronous condenser he can secure some, if not all, of the fol- lowing benefits: 1. Meet increased demands without the purchase of additional generating equipment — and by generating equipment is meant not only the generators but the necessary prime movers and auxiliary apparatus. 2. Reduce the cost per kilowatt of additional transmission rat- ing. 3. Effect a material saving in present transmission losses. 4. Improve service by maintaining the required voltage. Up to 1913 the Rankin plant, now rated at 10,000 kw., was operated independently of the rest of the system. At that time the load had grown to such an extent, owing chiefly to large individual motors and electric furnaces, that it became neces- sary to parallel with the main generating station at Brunot's Island, where the rating is 115,000 kw. This was done originally through two 11,000-volt lines. The central point of the load was then approximately midway between the two stations so that only about one-half of the line impedance came into the regulation problem, and it was possible to maintain fairly steady voltage at Rankin. During the last few years, however, the load grew so rapidly that it became necessary to deliver power direct to the Rankin bus for distribution. Two 22,000-volt lines were in- stalled between the stations, having a combined capacity of 16,000 kva. The drop in these lines at full load is approximately MANAGEMENT 289 13 per cent. The problem which presented itself was how to obtain the best possible regulation in the 11,000-volt transmis- sion network feeding from the Rankin bus, the load being ap- proximately 10,000 kw. and the power factor ranging from 70 to 75 per cent. (The engine-type generators in the Rankin plant, which have been in service for a number of years, can be operated at low power factor only at reduced capacity.) To accomplish the desired results at minimum expense, and at the same time provide for probable future increase in load, it was found, in view of the low power factor, that the installation of a S3^nchronous condenser for corrective effect would actually re- duce the transmission investment required per kilowatt, so that a condenser at this point was warranted on basis of transmission rating alone. A 7500-kva. unit was chosen which will permit operating the tie lines, when fully loaded, at a power factor of 90 per cent. The particularly interesting feature in connection w^ith the 2 4 6 8 JO 12 14 Kilowatts Transmitted. Jhousoinds Fig. 91 — Load and Regulation Curves present method of operation, made possible by the fact that the tie lines are not yet loaded to their rating and that the present load conditions do not require the full rating of the condenser at zero power factor, is the use of this machine as a voltage regu- lator. The Rankin plant is now run at practically full load witli power factor of 90 to 95 per cent, and the voltage regulation of the station is taken care of entirely by an automatic regulator 290 CUTTING CENTRAL STATION COSTS controlling the condenser exciter, it being the only one in the plant. The regulation of the entire network, therefore, is af- fected automatically by the value of the magnetizing current drawn by the condenser. The accompanying curves. Figs. 91 and 92, prepared from the transformer and line characteristics, will show the voltage com- pensation, or regulation, which can be obtained, the line amperes and line power factors, as follows: (a) Inherent regulation, two lines in parallel, to 16,000 kva., 70 per cent power factor. (b) Inherent regulation, one line, to 7750 kva., 70 per cent power factor. (c) Eange of constant voltage obtainable when using syn- chronous condenser from maximum lagging kva. to maximum leading kva. (d) Synchronous condenser loads, one line in service. (e) Synchronous condenser loads, two lines in service. (f ) Maximum load transmitted 7500 kw., both lines in service, maximum power factor 100 per cent. (g) Voltage range corresponding to curve (/). There are several fixed adjustments which can be used to add to the voltage regulation as conditions materially change: (1) The ratio of transformers may be changed; (2) one line or two lines may be used; (3) the old 11,000-volt tie line having approx- imately 20 per cent regulation can be connected in on exceed- ingly light loads. With one line in service and using maximum limits of con- denser it will be noted from curves (c) and (d) that the voltage can be maintained constant with load varying from 3100 kw. to 7400 kw. Under load of 7400 kw. the maximum capacity of one line is reached, so at this point the second line is put in service, as shown by the arrows and dotted lines at curves (d) and (e). When the two lines are operated in parallel and using the con- denser between its limits, constant voltage is obtained with load varying from 7400 kw. to 14,400 kw., as indicated by curves (c) and (e). With load of 14,400 kw. and condenser operating at maximum capacity leading, the power factor of the line is at its maximum — 90 per cent — and the lines are fully loaded at 16,000 kva. When the maximum load is only 7500 kva. and 100 per cent power factor is obtainable, it will be noted that flat voltage range MANAGEMENT 291 is materially increased, but since the allowable drgp is reduced the transformer ratio must be changed. While the curves show the limits of constant voltage with the condenser in service, it should be noted that it is very undersir- able to run the machine at lagging power factor, since it reduces the power factor of the plant, which is already objectionably low. Upon referring to the power-factor curves, especially the one for one line, it will be seen how rapidly the power factor drops when the condenser is drawing lagging current. While provided with a direct-connected exciter, which was also designed for use as a motor for bringing the machine up to synchronous speed, should this method of starting be desirable at any time, the condenser is self-starting and is equipped with an oil-pressure outfit for raising the shaft up from the bearings in order to eliminate the bearing friction and thereby reduce to a minimum the current required from the line, which otherwise would be comparatively large in amount at the instant of start- ing. With the oil-pressure outfit in operation the machine can be brought up to synchronous speed without drawing more than 1800 kva. to 2000 kva. from the line, as compared with 7000 kva. required when starting with the bearings dry. A pressure in 500 J 400 L. O 300 200 ^ ^ ./ / r^ « ( r^ ^ ^^ \ P •^d- "CA^r r^i ^ < f "^ r-1 — -J^e / / ne) ^//7e Cur •ren t->-1 1 100 80 o J. 60 40 4 e 6 10 12 J4 Kilowc^tts Transmitted, Thousands Fig. 92 — Line Current and Power-Factor Curves the neighborhood of 100 lb. per sq. in. (7 kg. per sq. cm.) is re- quired actually to lift the rotating part and provide an oil-bear- ing surface for the journal. The equipment consists of a motor-driven duplex pump for each bearing and the necessary high-pressure piping. The cyl- inders are connected in pairs to a common pipe running to each 292 CUTTING CENTRAL STATION COSTS bearing, the oil returning to the pump chamber by an overflow pipe. PREPARE HONOR ROLL FOR UNINTERRUPTED SERVICE An honor roll is being compiled for those Doherty properties which give uninterrupted service. The names on the list are obtained from the weekly reports of the various properties, in which they state the number of interruptions to service during the week just past. Seven companies were on the honor roll for giving perfect service for the two weeks ended Dec. 10, 1918 ; i.e., the Cumberland & Westernport (Md.) Electric Railway Company, the Durham (N. C.) Traction Company, the Hatties- burg (Miss.) Traction Company, the Lincoln (Neb.) Gas & Elec- tric Light Company, the Lorain County (Ohio) Electric Com- pany, the Massillon (Ohio) Electric & Gas Company, and the Montgomery (Ala.) Light & Railway Company. This information is sent to all of the properties in the or- ganization and helps to promote competition in the matter of service. The same idea could undoubtedly be applied still fur- ther in some degree to district offices of electric light and power properties. CLEARING HOUSE FOR IDLE STOCK Realizing that it is difficult if not impossible to get new equipment under present conditions and desiring to keep down the investment in idle stock, some companies with electric service plants in various parts of the country have established clearing houses for idle stock regardless of whether it is new or used. Each plant is required to report its idle stock on hand period- ically, this information being published in booklet form by the holding company and distributed among its plants. When any plant is in need of equipment included in this list it can com- municate with the plant having the apparatus or material or with the holding company. Thus equipment can be obtained in a very short time compared with most manufacturers' deliveries nowadays. Furthermore, very much less reserve stock has to be carried. MANAGEMENT 293 SALESMAN'S ASSISTANCE IN SELECTING TRANS- FORMER SIZES The central stations are more conservative than formerly in making extensions, owing to their exorbitant cost, and many are asking the prospective consumer to pay a part of the expense. It is well known that the more money a '^ prospect" is asked to advance the harder it is to close the contract. It follows there- fore that any information which the salesman can gather that will tend to decrease the expenditures will make it easier to do busi- ness, writes A. G. Drury. The primar3' function of the construction department is to build and maintain the lines as economically as possible, and any assistance which the commercial man can lend in this work by his knowledge of the character of the power load to be added is likely to be appreciated by the superintendent. One way in which to assist is in the selection of the size of transformers. It is evident that if at the end of the year the reports show that 2000 kw. connected load has been added to the system with 1000-kw. transformer capacity, it is better than adding 2000 kw. and 1500 kw. in transformers most of which are underloaded. The advantage exists not only in the amount of capital saved, but also in the amount of energizing current required by the smaller transformers as compared to the larger one. As a concrete example there is related an incident which came up in connection with a contract for supplying electric energy to a company which made small brass and bronze casting cages such as are used in receivers' booths in banks, etc. The equipment which was to be driven by motors consisted of an elevator, a blower for gas furnaces, emery grinders, polishing machines, lathes, a milling machine, drill presses, etc., in all twenty-four such pieces of apparatus. The total number of motors to be installed amounted to 42 hp. The salesman had become familiar with the character of the work and reported that he had secured a 15-kw. maximum-demand contract. The manager accordingly ordered three 4-kw. transformers. One of the men in the office, knowing the motor equipment to total 42 hp., out of friendliness to the salesman told him that three 4-kw. transformers had been ordered, when there should have been three 10-kw. machines. 294 CUTTING CENTRAL STATION COSTS Upon inquiry it developed that the rule was for the salesman to report 40 hp. or 30 kw., upon which three 10-kw. transformers would be purchased, whereas with co-operation established be- tween the two departments considerable saving in equipment would be accomplished. The difference in first cost is as follows : Cost to purchase and erect three lO-kw. transformers.... $271.50 Cost to purchase and erect three 4-kw. transformers .... 144.00 Saving in first cost $127.50 A test made on the installation mentioned after completion showed the maximum demand to be 12 kw. The salesman by studying the characteristics of any new busi- ness can save as well as make money for his company. From considerable experience similar to the above Mr. Drury has found that the capacity of the transformers serving an installa- tion can often be limited to less than a third of the connected load; but the salesman must make each individual investigation himself and not rely on the published tables of average load or maximum demands for different manufacturing businesses. The time and energy invested will be justified by the returns. SAVING TIME IN VOUCHER FILING The Agawam (Mass.) Electric Company and affiliated central stations, under the management of the Cabot interests of Boston, file vouchers most conveniently by making use of a method which is described in the following paragraphs : Vouchers are properly classified under account numbers and are then kept in manila envelopes about 9 in. by 11^/^ in. (22.8 cm. by 29.2 cm.) in dimensions, the face of each envelope carry- ing all account titles and numbers, with space for amounts and totals under each class, as shown in Fig. 93. Provision is also made for approval signatures, and a record of the check number paying the account and other information can be inscribed in the open spaces which are left on the en- velope to serve the convenience of this office. MANAGEMENT 295 CarrAt Pgrchucd 1 UMr •! Sub .uica » k^ Bel PUni E4P« 5ub-*U ■• * t.(«ti9i>t»inlio. 8M| » Oil Md W»jt«— Sub »utio«- ■ »•■ • ■ .•...[. T ••< A SubMJ . . » > •'■■ - * T«i«l ¥.««firt«<«- ■ ounaunoM MiUl Co» Li -Ub« ■ ' Ht.cil Mm..-UI>«i .1 Smmi A . . . ■ »f(k>n-vf » . ■■ Tm.ac C .Knd>B( U...t Mcirra-Mitttiil t M«.al M S L -Ubm » -'::. :-::-:■ -To»T.iiJAp» • " — TT»«!of»tt». t Rrp«lrt of Pota iBd Uon 11 Milal M 5 L-R>a »lp«rt» ■ " M.,.< Co» Po... 13 »ca»..l.«(C>m Uaip> 1* • .IMU4. •• , •• 14 •Slual «..aU«. .: ...M» ■.■■■: ■ . Aft>p~< »» PwaiaM. » -^ OBteiAL exroiM ■ " a ■■— - ^ D^mror.- Ano.a««... *• • CHECK HO Lfx*i P^P«a« * 0*« P.iprfeat •• Ta»ta » CUrtTt OA(*M> SaIaH« • _ TrecviBf K«« BnalMM • k__ t>. KU Vosckrn PajrabU > rmr tub CoBtuatuv L«0|a 1 * Toul<%HIU > *" ' ' " Mttli.pta I C L»»p« » '**'*" Uul»pl< I H U»p. « AiitoAtofetlw — ^ ' Sub >ta Bidff .--.- < » .Einl Pit Eq Sub^iU. - ■- ^ TT»nf Ui>«— 1)000 V»IU... *• V.m« ... ' ."' , Mon Si Lit Efl S«t«« • mtcetXANeout 0«c« P.iiofrt 10 ■ 1 ft Ld 12 T»U attd A pp DliUib 13 K C t ^ yu iJ!^ p hi* TnMlcfBcra le-« ■ I'' VoDcbm tr . . ...i. Fig. 93 — Face of the Envelope for Filing Vouchers Which is Used by A Massachusetts Central Station ECONOMY OF KEEPING RECORDS OF LABOR AND MATERIAL A scheme which encourages employees to economize time and material has been successfully developed by the Spokane (Wash.) Heat, Light & Power Company. The idea developed primarily in connection with construction work, but has been extended to include practically all operations where labor and materials are involved, even to firing boilers in the central heating plant. The plan simply requires an advance estimate of the cost of any work to be done, and this estimate, embodied in a written work order, is given to the foreman or that employee who has the particular work in hand. Thus the work order becomes a bogie to the foreman and he endeavors to keep within it if he can. If he exceeds the figure set, he has to secure authorization for more expenditure, and his explanation of this situation brings out either (1) unforeseen conditions, which aid the estimating depart- ment in future work, or (2) evidence of waste which the fore- man must clear up to the satisfaction of his superior. The advantages claimed for the scheme are that, in addition to the actual money saving, the psychological effect is excellent. Foremen dislike to exceed estimates and be obliged to explain 296 CUTTING CENTRAL STATION COSTS why, and on the other hand they take pride in keeping the cost below the estimate. There are also the advantages of an accu- rate record of costs conveniently arranged, an allocation of all charges for labor, a constant check on materials on hand, and a means of making up the payroll easily at any time by totaling work-order records. There are several forms about which the system centers. These begin with a letter size form known as the A. F. E. ("authority for expenditure" — Fig. 94), on which are entered the name of customer and a brief statement of the work to be done, with a list of the more important items that will be required on the work. It also states the amount which the work is estimated to cost. Before this A. F. E. sheet receives a work-order number and the work is classified it must be signed by officials of the sales department and the accounting departments, as well as by O o To General Office: Spokane heat. Light & Power Company AUTHORITY FOR EXPENDITURE HCAT-LICHT- POWER CONSUMCn 9_ RCVCNUI, S. CONSU RCVINi IN THe ESTIMATED AMOUNT OF_ IN THE ESTIMATED AMOUNT OF_ IN THE ESTIMATED AMOUNT Or_ TOTAL. »_ CHARGEABLE TO _^ CHARGEABLE TO CONSTRUCTION t ( OTHER THAN TO (DESCRrPTlON IN DETAIL MUST ALWAYS BE GIVEN ABOVE. OUHATION or WOAX •« Puebiu, Colo Jan ♦ 1st > 1918 - t3o Our Qusitomerg: ^Uf Uf to CfXtitp, That the bearer of this Card Ml8s Ruth Barr £$ employed by this CpvnPany as ^Qter R6fider Cn»t««ier* will pSeoae admit him to their premites at reaionable hoar* ior the ^unpose of reading, teating or inspeotiotf meteri or mabisg a«