; ° < a i ‘ i x ‘ ze 5 8 zZ 4: y Dia :: y 4 - ; 5 ae “ Sane sy ‘ t 4 ; ee 5 : $ 5 i a Pie set = : ay Pied i i i “ y AND REPAIR gece a z 3 ety 5 28 ® $2) £ Ht r ge 5 fay iy ioe. , Bay % a s if) . ie +] “yh f Ll uo ae ys ‘ ‘ - re Ty) oo we ie G920 2 benen ge dws caged ergrue Oisges heh Geen ho? eeeounae. autes loeoogeg Shauerege ‘Mio aes he ee s 2 ® — s P INSTRUCTIONS. FoR THE. oe ‘ve = Os, rr 7, * AND®RI cnc ais Morons > s SAND MOTOR CONTROL PANELS ( Reprint of Chapter 24 of the Manual of Engineering Instructions ) NAVY DEPARTMENT BUREAU OF ENGINEERING Pi i¥ fi 4 #8 & E. gif Sie: ue 43§ ty DA wa mes S g e 5 my 4 2 ‘a ¥ : 14353 4 j i\4 / 43 bat & i” WASHINGTON GOVERNMENT PRINTING OFFICE 1924 * at a BP EARHA, 2 CHAPTER 24. GENERATING SETS, MOTORS, AND MOTOR CONTROL PANELS. Sec. I. Generators and motors—Articles 24-1 to 24-35, inclusive. Part 1. Operation—Articles 24-1 to 24-13, inclusive. Part 2. Care—Articles 24-20-to 24-35, inclusive. Sec. II. Control panels—Articles 24-40 to 24-70; inclusive. Part 1. Operation—Articles 24-40 to 24-49, in- clusive. : Part 2. Care and repair—Articles 24-60 to 24-70, inclusive. Sec. III. Periodic tests and inspections—Articles 24-80 to 24-98, inclusive. Part 1. Generating sets—Articles 24-80 to 24-83, inclusive. Part 2. Motors—Articles 24-90 to 24-93, inclusive. Part 3. Controllers and control panels—Articles 24-95 to 24-98, inclusive. Sec. IV. Safety precautions—Article 24-100. Section I.—GENERATPORS AND Motors. PART 1.—OPERATION. 24-1. The instructions contained in this chapter are general enough to cover all types of electrical machines. In the case of the more important auxiliary units, specific instructions covering operation and assembly are issued in the form of pamphlets by the manufacturers, and these should be made readily available to the personnel who operate, care for, and repair them. The bureau arranges for sufficient lithoprints or blue prints to supply each ship with a general arrangement plan, and sufficient detailed plans to enable the ship’s force to handle most of the ordinary repairs likely to come up in operating the various electrical units. These plans should be carefully indexed, kept up to date, and should always be referred to when machines require overhaul or repair, or when ordering new parts by requisition. 24-2. (1) (a) After assembling a machine, a final inspection Pamphlets and lans. Inspection after assembly, shall be made to guard against starting with loose bolts, improper before starting. clearance, short circuits, broken insulation, or any damaged parts. (b) The binding wires shall be examined all the way around, especially those on high-speed armatures. (c) The air gaps should be equal, as measured under poles of the same type, and poles should be uniformly spaced between tips. (d) The armature clips on both ends are easily bent out of shape when handling and it is essential that these leads be straightened and uniformly spaced before starting. (e) The use of two sets of series field connection strips, one connected to each polarity of the machine, usually without the 0 48824 24-1 24—2 Inspection after assembly, after starting. Starting a generating set. CHAPTER 24, interposition of circuit breakers, necessitates extreme care in guarding against short circuits. In case of a short circuit between these strips or coils the machine would build up as a series generator with absolutely no protection other than a burn out or shutting down. These parts are carefully designed for ample clearance, and suitable spacing blocks are-provided to maintain these clear- ances; but there is always a possibility of strips or leads being bent out of shape while handling, and a very careful inspection is there- fore necessary before starting. (f) Commutators are frequently fitted with radiating vanes, for cooling, and these vanes should be examined to see that they are properly separated and that the stationary vane guard is assembled with the proper clearance. (g) Slotted commutators should have the slots cleaned out as an insurance against bridging between segments. (h) Brushes should be adjusted to an equal tension of 1} to 2 pounds per square inch each on the commutator brushes and about 4 pounds per square inch each on collector ring brushes. The brush holder studs should be checked for their alignment with the armature shaft and to see that they are rigidly secured to the rocker. The holders in turn should be securely clamped to the studs. The brushes should fit in the holders snugly, but not so snugly as to bind. Check each pigtail to make sure it is not loose. Such looseness is a frequent cause of abnormal brush heating. (i) Inspect the lubricating oil system, and see that sufficient oil of the right quality has been supplied. (2) (a) On starting up, the speed of the machine shall be care- fully determined to see that proper speed is maintained. No chattering or undue vibration should exist as the load is thrown on or off. (ob) The eommutator or collector rings should run true and smoothly without chattering of the brushes, and all sparking should be eliminated. (c) If a lubricating oil cooling system is provided, the tempera- ture of the inlet and outlet oil should be taken until the running heat is established, and if the temperatures are excessive the trouble shall be traced out and remedied before extended running is undertaken. Samples of the oil should be frequently taken, and these should be examined for metal dust from defective bear- ings and for the presence of dirt in the system. Oil should be renovated until the system runs clean.’ Examine the automatic oilers and the oil rings and make sure that all are functioning properly. (d) When the set is in operation make frequent inspections to see that the oil cooler is getting circulating water, and examine the oil to detect any water resulting from leakage in the cooler. 24-3. The steps in starting a generating set are as follows: (a) Examine both steam and electrical ends to see that all rotating parts are clear. Turn the armatures of small generators one complete revolution by hand. (b) See that the commutator brush rigging and brushes are clear, and that the brushes react to spring tension. GENERATING SETS, MOTORS, AND MOTOR CONTROL PANELS. 24—8 (ec) See that all switches are open and that the rheostat handle is so set that all field resistance is cut in. (d) Start steam end. (See instructions for driving units, ch. 30.) (e) Bring the machine up to its rated speed and see that voltage is normal with the rheostat in low-voltage position. . (For pro- cedure if voltage fails to build up, see art. 24-5). (f) Build up voltage until it is three or four volts higher than a the bus voltage. . (g) Throw in circuit breaker. (h) Throw in equalizer switch. (i) Throw in negative switch. (j) Throw in positive switch. , (ix) Regulate voltage to divide the load properly. (Indicated by the voltmeters of the two or more machines in operation). 24-4, The steps in securing a generating set are as follows Cutting out a (a) Take most of the load off the machine to be secured, by Senerating set. field rheostat. (b) Trip circuit breaker. (c) Open positive and negative switches. (d) Open equalizer. (e) Put rheostat in position where all resistance is cut in. (f) Secure steam end: (See instructions for driving units, ch. 30.) (g) Blow out armature coils, commutator spider, and air gaps, etc., with compressed air. (See art. 24-26.) 24-5. (1) In case a machine gives the opposite polarity to that veltsen tele ne desired when building up its voltage, separately excite the fields build up. with the correct polarity to reverse the residual magnetism. This is done in the following manner: First, disconnect the brush leads at the headboard; second, on the machine panei throw in— (a) Shunt field switches, if used. (b) Circuit breakers. 4 (c) Common negative switch. (d) Positive light or power switch. Momentary excitation is sufficient, so that a moment after closing _ the positive, the circuit breakers should be tripped, other switches pulled, and the machine again made ready for normal operation. Failure to build up voltage is sometimes due to an open point in the shunt field circuit and sometimes to reversal. of the shunt field connection with respect to the armature. A reversed field connection can usually be detected by the residual voltage tending to approach zero when the field switch is closed, and this indicates that the diagram of connection drawing has not been properly followed in the wiring. (2) If found properly connected, it should be assumed that the polarity is actually reversed. Shut down the machine and sepa- rately excite the fields with the correct polarity to reverse the residual magnetism as described above, obtaining excitation from another machine. The resultant polarity must be checked after every separate excitation. 24-6. In operating a generator, keep the voltage constant and Constant volt- the load equalized by the field rheostat. If the voltage is such *5* that an excessively low or high position of the field rheostat is required, the speed of the generator shall be checked. 94-4 Checking read- ings. Running at overload. Parallel oper- ation Mechanical balance. one of brush position. CHAPTER 24, 24-7. Oil gauge readings and bearing temperatures shall be frequently checked. The oil should be changed, and filtered or renewed periodically, and each time the fact shall be entered in the log. If an oil-cooling system is installed, constant vigilance is necessary to detect promptly corrosive punctures or leaks in the cooling coils, which allow the passage of salt water into the oil. (See ch. 10.) 24-8. Navy standard generators are designed for 25 per cent overload for two hours. However, this extra capacity should always be considered as a safety factor and machines shall never be habitually run at a greater than rated load. When necessary to operate generators at greater than rated load, inspect all parts such as bearings, field coils, and brush rigging every five minutes for overheating. 24-9. Any difficulty met in obtaining satisfactory parallel operation is usually due either to differences in compounding or inequality in the resistance of the series field circuits from the equalizers through series fields and cables to the bus. A slight unbalance in the resistance of the two circuits would result in an unequal current flow, so that the machine with the lower resistance series field would carry a greater share of increase in load to the extreme of throwing out the other machine entirely. A simple resistance determination will disclose this trouble, and the remedy consists in shunting part of the flow in the heavier field. Slug- gish or erratic governor operation is often a cause of the difficulty, and the remedy lies in a careful disassembly, cleaning, and over- haul of the governor. (See ch. 30.) 24-10. Any appreciable vibration should be located and cor- rected as soon as it occurs. All rotating parts are carefully bal- anced at the factory, and an investigation of balance trouble should therefore consist of a careful search for misalignment, sprung shafting, or something chafing the rotating element, before shifting any balancing weights. Brushes sticking in the holders have been known to upset the balance. Balancing pockets in the armature flanges, in which lead can be peened, are provided for correcting any unbalancing of the armature. 24-11. After running a short time, the appearance of the brush faces will indicate whether the brushes will soon wear to a proper fit over the entire surface or not. Any of the brushes showing a fit over only a very small area should be sandpapered again. It will be found that reliable results in compounding tests can not be obtained before the brushes are all thoroughly fitted. Shifting the brushes around the periphery of the commutator has an effect on both the compounding and commutation. In a generator, the armature current reduces or increases the main field magnetiza- tion, depending on whether the brushes are ahead of (shifted in the direction of rotation) or behind the true neutral point, thus hav- ing considerable influence on the compounding. In order to pre- vent sparking, the brushes must be held in such a position that the armature coils short-circuited by the brushes are under the influence of the commutating poles, but occasionally shifting from an exact center to produce slight changes in compounding is per- missible. Even the most careful setting with the tram is subject to slight errors, and as a final adjustment, when working to very && Led GENERATING SETS, MOTORS, AND MOTOR CONTROL PANELS, 24—5 close limits, slight changes in brush position may be necessary. On a machine that is running, care must be exercised, when shifting brushes, to guard against raising the yoke out of its support, which would pull the lower brush holders into the commutator and cause serious damage. In spite of these instructions, how- ever, machines should habitually be operated with the brushes set at the neutral point at which the machine was initially compounded and adjusted. The necessity for a departure from the manufac- turer’s punch marks is a trouble indicator. , 24-12. Sparking may occur at the brushes for any one of a Sparking. number of reasons which are itemized and for which remedies are discussed under article 24-31, As soon as sparking occurs the conditions which cause it should be rectified, as these conditions will rapidly become aggravated. 24-13. The same method of operating switches at the switch- eet iaaes oie board should be employed by all members of the dynamo-room | force. PART 2.—CARE. 24-20. (1) Keep both the interior and exterior of a generator Cleanliness. or motor free from water, salt, lint, dust, dirt, and particularly oil. Do not allow oil to enter the machine with the cooling air and thus be deposited on the windings. An excessive accumula- tion of dirt may eventually ground the coils and burn them out. Dirt, aside from restricting the air flow, is a heat insulator. (2) Particular care should be taken to guard against carbon dust from brushes and copper dust from sanded commutators. (3) When cleaning a machine care must be exercised not to crowd dirt into narrow spaces between conducting parts, or in the air ducts. (4) Care must be taken in filling oil containers on ring oiling motor bearings that the oil level is not so high as to result in leak- age along the motor shaft. Filling these bearing oil containers too full causes overflow into brush rigging and lower field coils and ereeping of oil into interior of spider and thence to commutator and windings. 24-21. Should dust or dirt be lodged with oil on the coils, re- Bed tt dust move it by means of a cloth dampened with carbon tetrachloride ‘ (Pyrene liquid), taking care not to touch the steel parts, as corro- sion will develop due to a combination of moisture and carbon tetrachloride with the steel. Remove all salt deposits from the machine. Clean rags, or preferably cheesecloth, shall be used in all windings. The use of any material which deposits lint must be avoided. 24-22. The use of paint on the insides of field frames and Painting. housings eventually results in paint getting on field coils, leads, and brush riggings. As ordinary paints usually contain materials of a conducting nature, such as white lead, they must not be used in the vicinity of windings or any live parts. This precaution applies particularly to open motors, brush rigging, and electrical panels. On the above-mentioned parts the best grade of insulating varnish shall be used. All fiber insulating distance pieces and bushings should be carefully cleaned and scraped and coated with insulating ‘varnish. Electrical leads should be properly served, and should ‘always be painted with insulating varnish. 24—6 : CHAPTER 24, bot htening 24-23, All bolts shall be gone over occasionally to keep them tight, particular attention being given to the bolts used to clamp any insulation. Fiber insulation, used around brush holder brackets and collector rings, and wooden spacing blocks are sometimes used in supporting connection strips, and as this material is subject to considerable shrinkage, the bolts must be tightened frequently until the insulation is thoroughly seasoned. In setting up: cn brush stud nuts always check the stud alignment, as any throw of the end brushes ahead or back of their normal position will, cause sparking in various degrees. Unless a commutator shows evidence of loose bars the commutator clamping bolts should not be disturbed. Serious distortion of the clamping rings and segments is sometimes caused by excessive tightening of the com- mutator clamping boits, so considerable care must be exercised in adjusting them. | Stier tome 24-24. Most of the sparking experienced after a machine is in brushes. operation is due to mechanical defects, such as rough or eccentric commutators, or brushes not riding properly. If the commutator and rings are sufficiently true and smooth, the brushes will feel ‘“dead’’ when the machine is at normal speed. The brushes should be staggered to cause the commutator to wear evenly. If this is not done, the commutator will wear into shoulders and ridges which will finally necessitate turning down. When fitting new brushes, care should be taken that the brush fits its holder loosely enough to permit up and down motion, but not so loosely as to cause excessive wobbling. Commutator slots must be cleaned out occasionally to keep ali the mica weil below the wearing surface, special care being taken to eliminate all projecting fins or slivers. The use of oil on commutators is unnecessary except in rare instances where some of the older types of hard carbon brushes are used. With most of the modern brushes of a graphitic nature, oil is actually detrimental to commutation. Besides the effect on commutation, oil, vaseline, or other commutator lubricant should be avoided on commutators, as such lubricants have a tendency to work into the side mica, causing insulation breakdown and short circuits between segments. Commutators are slotted in order to use the modern graphite brushes, which have very desirable current- carrying and lubricating characteristics, but which will not wear mica down evenly with the copper. In general, therefore, it never is advisable to lubricate sictted commutators. The collector rings of machines using brushes of a metallic composition run at higher pressures than commutator brushes give, and best results are obtained on collector rings if a slight amount of oil is applied occasionally with a small brush or canvas swab. Just enough oil should be applied slightly to lubricate the brushes and produce a polish on the rings. Brush holder lever arms shall be inspected occasionally to see that the springs give uniform tension, and the brushes should be moved up and down to insure that they work freely in the boxes. An accumulation of dust has been known to settle in the clearance space around brushes and embed the brushes so tightly in the boxes as to prevent their removal without breaking. Brush holders are so made that the spring tension can be easily adjusted to keep the brush pressure uniform. As mentioned in article 24-2 (1) (h), the springs on the commutator brush holders GENERATING SETS, MOTORS, AND MOTOR CONTROL PANELS. should be adjusted to give 14 pounds per square inch each, and on _coliector rings approximately 4 pounds. Uniform brush pressure is a very important factor in maintaining successful collection of current from the commutator and collector rings. when working with electrical machines. If it is ever used, the limitations and instructions contained in chapter 38, with special regard to articles 38-149 and 38-150, should always be kept in mind. 24—7 24-25. Generally speaking, the use of gasoline should be avoided fies ae Peer 24-26. A compressed-air jet, or even a hand bellows, isa most Cleaning effective means of cleaning the windings of rotor or stator and for dislodging the metallic dust which accumulates between the commutator segments. A vacuum. cleaner is even more effective, but except on some of the latest ships is not usually available. Frequent use of such a device will save much expensive overhaul. Before using the air jet, the freedom of the air from water must be assured, and care must be taken to avoid the danger of driving srit into bearings. 24-27. Once a year clean the end windings thoroughly and apply - End windings. a coat of air-drying insulating varnish.. This varnish may be sprayed on by using compressed air in connection with an atom- izer. In varnishing windings care should be taken that no var- nish is blown into electrical contact surfaces where it will tend to insulate them and prevent current from flowing. During the varnishing operations all brushes should be removed and the commutator should be wrapped with canvas. 4-28. Keep the air ducts free from dirt; any restriction will Air ducts. seriously interfere with the flow of the cooling air and cause exces- sive heating. 24-29. If an electrical machine is to be shut down for any Prevention of period exceeding 24 hours, and it is provided with heating coils, the dampers at the air idle and outlet ducts should be closed and steam turned into the coils. This will heat the interior of the machine several degrees above the room temperature, and so prevent the accumulation of moisture on the windings and the working parts. Where electrical heaters are provided they should be used in preference to steam coils. Their use is especially neces- sary on large idie motors or generators during long periods of damp weather. Care must be taken with any drying-out heaters that the heat is evenly diffused and that local spot heating does not result. Many machines, due to peculiarities of location, are liable to an excessive moisture precipitation. In such cases, the use of an ordinary portable 40 to 60 wait lamp placed well within the frame and the whole covered with a tarpaulin is recommended to produce the necessary temperature rise where special heating facilities are not provided. Free circulation of the air through the windings should be assured unless these precautions are taken. when shut down. 24-30. (1) Overheated bearings may result from a number of Causes of over- different causes; among which the following are most frequently found: (a) Bearings out of alignment. (b) Insufficient oil. (ec) Poor-grade oil. 88188°—24—2 heated bearings. 94-8 a CHAPTER 24. (d) Dirt or grit in oil. (e) Gummed-up oil leads. (f) Poorly fitted bearings. (g) Bearings too tightly set up. (h) Scratched or corroded journals. (i) Overload. (j) Conduction from overheated electrical parts. (2) Dirt may cause the gauge glass to indicate oil when none is present, and a clogged top vent will cause the same effect; oil rings will wear out of round and fail to rotate; lack of end play will cause binding or heating, the trouble becoming aggravated as the shaft expands; a bent shaft will cause vibration and grinding at the journals. Ali these troubles should be guarded against by frequent, intelligent inspection. Until a machine is available for overhaul, overheating may often be checked by the use of a liberal supply of fresh, cool oil, or in emergency by the use of water, taking care to keep the electrical parts clear of either oil or water. (3) Inspection will usually disclose the particular trouble, and the remedies are obvious. epee | and 24-31. (1) Sparking at the brushes indicates a condition which * should be promptly remedied to prevent serious trouble. It may be caused by any one of a number of conditions, or their combina- tions, and oftentimes the character of the sparking will indicate the underlying trouble. The following table, with references to subsequent subarticles, is offered as a tentative guide in trouble finding, though it should not be accepted as final: (a) Ineandescence of the carbons (4). (b) High, white spark under one brush (6). (c) Periodic sparking (7). . (d) Blue, snappy sparks (9). (e) Ring of fire (9, 5). (f) Continuous heavy sparking (4, 9, 10). (g) Sparking varying with resistance (11). (h) Continuous light sparking (2, 3, 8). (i) Sparking on starting up (11). (j) Sparking at heel or toe of brushes (2). Off neutral. (2) Brush rocker ring at the wrong place. Set the rocker ring to the square mark on the frame. Brush spac- (3) Brushes wrongly spaced. This may be caused by a blow aah either to the brush holder or to the rocker ring, bending either out of true, or may be due to a poor setting in tightening of the brush- holder stud. A convenient method to test spacing is to cut a strip of paper until it fits around the periphery of the commutator, then fold it in divisions corresponding to the number of rows of brushes. Place this template around the commutator, and check the brush edges against the creases. . Brushcontact. (4) Poor brush contact. This may be due to high spots on the brushes, to the binding of the brushes in their holders, or simply to varying spring tension among the different brushes. With any of these defects the result is to reduce the effective brush area, forcing the actual effective area to carry excessive current. This will induce heavy sparking and often heat the overloaded carbons to incandescence. In the first case, place a piece of sandpaper face up on the commutator, and by revolving the commutator with the GENERATING SETS, MOTORS, AND MOTOR CONTROL PANELS, 24—9 brushes held in firm contact, grind the faces down to an even ¢. bearing surface. In the second, clean the holder, and clear the sides of the carbon of fins and ledges. In the third, even up the spring tension all around, bearing in mind that the brushes under- neath should be set up slightly tighter than those on top to balance the action of gravity. (5) (a) Commutator dirty or rough. The commutator should be Craning com- kept clean by wiping with light canvas, cheesecloth, or woolen eee a cloth, care being taken not to allow any threads to lodge on the brushes or between the segments. If carbon dust and oil collect on the commutator, they will give trouble. Once a dull, glazed, brown-black finish has been obtained on the commutator, very little further roughening will occur. It should be the ultimate aim of the operator to develop this clean smooth chocolate color on commutator bars. Sandpaper should be used very lightly on the commutator, if at all, and emery cloth shall never be used, as emery is a metallic conductor which, if lodged between segments, will short-circuit them. If it does become necessary to use sandpaper to smooth the commutator, the sandpaper should be fitted in a wooden block which has been shaped to the proper curvature, and should be held firmly against the surface and drawn in the direction of rotation of the armature. Projecting mica insulation will not yield to the action of sandpaper, and must be turned down with a light cut in a lathe, or by a commutator grinder, a finish being given with fine sandpaper. (b) Grinding at or near full speed is the best method of truing Grinding a or smoothing a commutator or collector, and if facilities are avail- °°™™mutater. able for grinding, this method is always preferable to using a lathe cutting tool. In grinding, a large number of very light. passes must be taken to insure a true cylindrical surface. Any undue haste or crowding of the grinding wheel will result not only in a rough surface, but often in a noncylindrical shape. During the grinding operation all windings should be protected from the deposit of copper dust, the field coils being protected by a stationary guard and the armature fitted with a canvas head securely bound on the commutator and armature surfaces. The ventilating spaces under the commutator may be protected by stuffing them full of waste, care being taken to remove this waste when through grind- ing. After grinding, the machine should be thoroughly cleaned and the commutator slots gone over with a sharp tool to remove any copper dust or bridges, and to smooth up the edges of the segments. (6) Copper embedded in the brush. A bright sparking appearing Metal in under one brush and gradually cutting a groove in the commutator pruanee is due to a particle of copper which has become embedded in the © brush. This reduces the local contact resistance, causing an abnormal current to pass at this point, which is shown by the spark. Remove the copper by scraping the brush face with a knife and sandpaper the brush to a fit. (7) Commutator bars, loose, high, or low. Bhat ad’ WOR faiths 6 ; Gi agertt havi’ rargipe ta Gi 2 asontvcen wom ty onifoant: 6d. b phone: berortens bebe ry » -boteaiumierend eved: seo rr Tasi viola wwoisseniveb oviioaton i dittoxis .goeul aes rogbtde dgoal a a AS aia Laqpend-tsv ei. vial Sit! i, iw fob ps SWOT os hae sd hele goon the ao stosleay. pbow . Cg. * me ion A. 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Se OE et Soa te eac ee ee eee oe 24-24 Conmnittarore cleaning and cringing. 2.) ose ete eee ei ee Bo el eee ee 24-31 (5) collectors atid, brusnes,| Care Of- 9 ee 9255 ee ASE ee ae eee ae eee 24-24 Sir ee ee) iene ee eS ES i. et eo eee Dee 24-31 (11) ULE CEU ULG tes oe es ee ee ee tes ESR S LR SATIS Se Oe et en ree 24-31 (7) GManteouor tests Ole too. eae tee a eee en lee aie Le te Te et BS Se oe 24-95 to 24-98, ine. D. SON ee ee ee 8 TO sa oe ee hae ee Uewetoke aoe 2449 Or COMtbolers..care Of deVviceses a 4 selene. 22k ek oot iN eae oe i es Se Coen tee see BS te 24-66 WENGLAl CALE .Ob semis Aas TORO LEED ein ine Mey SOE Os oo oe Se Se ee De 24-65 Pera ot eoneravors. and Motirsies "32s Se LS ee et ee eee. 24-29 E. ie eee ION ge ape ee ent Se is Ok caelen poe ea SASY > oe SORE Somes Seem 24-11 FileGeMatte ee CALD Ol pea = oes ek eee ee ee Cs | eee 2 ey eee gen en ome 24-27 F. TRF ISG a co eka ps Bt pS RNR Bt SOP ln 0 el Lg Ee RR EA eR ay ergo a CR pay ee em 2 24-70 G. DumeeeALLICe OE fOr IGANG) ot eke 2 ets Ss ee es Bee he a ao aba eo eee 24-35 Generating sets, constant voltage necessary - - -. - -.-------------------------------------------------- 24-6 failure Om volbalD CO DUNG MI Dise se oe ee eer ee os ee eee oe on ee 24-5 c[Sfe Dhiba (esto) tke ayo sh ny ee ao ER ae ty cca ele ie ee Sete Pak a PRR a a of 244 et SLT re anes eae ine Se yt SS aR Ce meat alk, Sem RE nie woe 24-3 SOS USL Ole ee ee Cam: Soe. et ath ee re ate Sw 24-80 to 24-83, inc. Grounds,, due to; moisture. in: coils. 22... 5-21... -----252--225-2-- 22-352 +2 ba ane 24-31 (9) (d) H. Pines wmracinatur e222 tos oot eb essa ee eb oho 7 hwo - 5 ee Ss en eh ee gas 24-33 peas at MOU Oe ITC LOL. oa 2 ee ee eas eee Renee ese a eae wee on 24-44 Pan as we a eg Ec Senin don Rida we geek = gabon nae pe ean dee Seg h anak eee tee 24-31 (8) 24-21 > Seah ae rte sc a oe a DA OSA ne wk Bae om " + a oF ee 2) : m | Fa aes ees Article. § Tppeetion, generators and th dkors: after assembly after ON ee ee Os eee 24-2 (2). | ARDAGA © before starting 2 -----o+------- — ¢f ee tee IM rss ek Staet ee Ve Gb. nod Tage Mechanical balanaah WAN ee ee ec ae a elie eee: ; Moisturectyt vention of. ei Qo ee a Mile dois a aang wre : Motors, fatnire to Start gt Ss So he UN ee. hee a cplte Sop Ss ey chi 2 eae gam aman BEATA S Ole Fk tere gee Ne oe ea sei ane ar a PTE nae Cee aN ee Matas spe ae SEODDINE Oli wae eh te tke See een eta te Se tle ce ee a : tests: Ol ie Feet oa ee ede sere Oe Set ae ae ae ad ate ee 6 “83, ines O. isis! Since Qil systems, checking and cleaning’. 0 = a Cul ge Ot Broun PANers. cits ei Sa, ales et lk nee e ootne dace Eh pr eee ee ee ON ite oe ne Operation of switches and Teyérs.c2 92-02 SS rer or a ce dena a cae 243 Overheated bearings? catises Of2 2 a ee ee ee ee Overload .as7a cause “Of sparking: 25“ seer se ee ea ee a ee ee ee ee ___. 24-31 (10) Overload blowout of motor-___----- sf ae gw ge ree SE rE a ee aN a ver oad; FANNING Bhi ce Sn Se ee tee enc ed nS Es ee NM ort fs eon Pe PAINE -COHOTALOLs ANG. MIOLOLS nome ook! oe See ee ee ene See eee Pamphiets and plans, tise, of. 2020 V. at a a ee a Paral Govts te tos pede a See sao cee sale u elas va ob he vecw nage ae a LUlDe 2a Panel surfaees,-care Of. 22-2 eel eS ei ee Pyrdisptare of devices o-oo. oe eae eee ote baie wes wh aee on oad 5.8 oe penéral care Ol... oo) 85 A eS ie a en 60° OSES OF oe ee a Ss ee eo ee are si ee gi ene _. 24-95 to wae. ine: use of oil around__-_--___-_ ian One nite a Serene pose eget pharma eee re iis dn cera ee Perallel-operation. of generators. - 20°. fe ucs ol es 2 Soe ee ee ee Bersgunel, stationing Of. 2... st... eee Ga ee gee Rare ERE CAN Ss ore. Poles, Temoval Of... oss t eins to mee oe ee ee ma oe ear eee - Readings, vause-and temperature .2.- sx. e sce aot ee, eee ee halen Hemoval: ot polesucs 222 S38 cee Se eee ee eee OR ee ee eRe, LS Mea IS “9 Rheostats, genre Of... 2. o +. 2 ee oan tL cee ees owen a ree eas Gk eee ce eo Ranping. at.overload._.... 200 Ue ee a Safety PReeaULIONS: se Ss eae oe oD eter es ee irae - 24-100 Securing-& penerating set. 02 ue LSS oe ee ee ee es es ee Setting of armature for concentricity_________ os Bar Ny To oR rn REE gO es ee eat 0 ee | “So Bparking .-- 2222S eee eC Se oe ee age a ee Sparking, indications, catises, and remedies. 20°2. 2002 2 eee Startirie’a venerating set. 05222 l cos 2 NS a a ee Rtartine e miotor ose a a oe ee ree ac vo a See tes ae a 24-40 failure Ins Se ee ee Starting resistance, automatic contactor paneles: co: - 2-2 sealer eso sac sek ee Blopping-a. generating set... cy. ee ALL eee eo ee ae BERRI A TOL ona eens tner tee ooh acces Voom ee arena iced aa Switen and lever-operation... . 6202 oe See ee ~~ 2h 4-43, Sywitehboard manipulation 22. 22s 5 ck Ee ee ee eee smigches, Care Of 201 J ocus 0. oss ed ooo eee a nS Oe eg sroseectesnsnceset 24-02 . E. Bile Leste ot eonirollers. oo 25 9: 220. Se Saku a ace a ei = ER gene 24-98, ine. gererating sets) clase eo Rete ees Oe ea i 24-80 to 24-83, ine, MHOCOTS. 25 So esse asc Ebeling condones ca oe aes oe eee eae gee ae ee 24-90 to 24-93, ine. PONOIS | oh ways We Se oe ae kane a re tie ee ae ee a ea 24-95 to wee inc. Tightening DOS poi rots Feces s crs Sa ee ee ie ot a oo oe Se ee ee U. Use of-wiring diagrams :22 sss soe) Poe oo ere se ee ee ue ye Voltage, constant required om generators 222 et fr ee falureto build up site es i a ee Ww. FRO OUI St sins Seas ane Fe ah NG Soe eee Bene ea De ig eee te wate oie eae cia oe 24-31 a Wainidings, cleaning Of, 2225 Se Sar ee ee ee ONG, Care Of fo.c2 2. Se Sok eR ees oR ye a ree ae eg Wiring diagrams, use of Yoke, brush, position of od * ‘ Spe A eer SO, te 2 Oe OM oh. : : Eata Ssh et a ~ =O p= osM pao?