None
around armature, 361 Motor, motors commercial eflaciency, 348 compound, 244 as generator, 247 • control, 252 Day, 258 Leonard, 256 Panel, 260 counter B. M. F., 236, 237 efficiencies, 247 faults, table, 504-508 fundamental equation, 239 losses, 250, 251 operation, 252 problems, 263, 264, 265, 266 series, 243 control, 253 regulation, 244 shunt, 240 connections, 240 control, 2o4 table of faults, 504 theory of control, 231 general principles, 231 torque, expression, 235, 236 used as generators, 245, 246 Motor circuits installation, 629 size of wire, 622 Motor generators relation of B. M. F.'s. 313 Motor turbine interrupter, induction trana- former, 552 Multiple grouping of cells, 64 resistance, 46, 47 series grouping of cells, 65 Multiplier shunt currents, 106 Mutual induction, coefficient, 158 Needle compass, 115 Bvershed testing set, 443 Nemst lamp, 380 Ness intercommunicating telephone system, 539 Net efficiency of motors, 250 Nickel constituent German silver, 38 electrochemical series, 54 paramagnetic, 122 Noise running dynamo machines, 326 Ohm megohm, 24 microhm, 24 practical unit of resistance, 24 Ohm's law, 23, 96, 98 application to simple circuits, 98, 99 problems, 96, 97 Ohmmeter, 440 coils, 441 insulation resistance 487 Index 631 OUs table of insulators, 51 use, 52 Olconite use, 52 0]>en circuits locate, electric fault finder, 518, 519 Operating In parallel, instructions, 228, 229 Oscillations, electric, 547 damped, 544 feebly, 545 strongly, 545 definition, 544 high frequency, 547, 548 induction coil for creating, 161 intermittent damped, 544 production, 544 sustained, 544 transformer, 571 Output Brackett's cradle, 485 Edison storage battery, 93 generators, 194 limit, 198 secondary cells, 81 Ovemmning generators, effect, 372 Oxygen electrochemical series, 54 Panel, panels control of motors, 260 Parallel charging of secondary batter- ies, 85 connecting compound ma- chines, 224 connecting series machines, 227 connecting shunt machines, 225 generators, 221 operating, 225, 226 resistances, 47, 48 Parallel circuits alternating currents, 291 diagram of, 293 E. M. F. triangle, 299 example, 294 vector diagram E. M. F., 300 Paramagnetic substances definition, 122 Partial conductors table, 34 Period definition, 268, 544 Permeability magnetic, 123 coefficient, 123 Phase definition, 269 Phosphor bronze table of conductors, 34 use, 35 Pierce wave meter description, 579 tuning, closed sending circuit, 582 tuning, open sending circuit, 583 Paper table of partial conductors, use, 52 34 tuning, receiving cii Plants cells, 76 Paraffin table of insulators use, 52 Platinoid specific resistance, 97 633 Index Plates definition, 55 negative, £:di8on battery, 90 negative, secondary battery, 75 positive, Edison battery, 90 positive, secondary battery, 75 Platinum electrochemical series, 54 melting point, 39 resistance, annealed, 38 specific resistance, 37 table of conductors, 34 use, 35 Platinum silver resistance, 38 table of conductors, 34 Pings testing set, 474 Polarity pole pieces, search-light elec- tric control, 408 rules for, 130 Polarization primary cells, 57 Pole, poles cell, primary, 55 effect of increase on E. M. F., 269 magnetic, earth, 115 north, north seeking, 115 south, south seeking. 115 unit magnetic, 16, 119 Pole pieces, 184 Porcelain table of iPBUlators, 51 use, 51 Potential difference, 20, 21 fall, 20, 21 around armature, 363 magnetic, 137 Potentiometer, 446 connections, 447 diagram of connections. 447 elementary, 448 uses, 500 calibrating ammeters, 503 calibrating voltmeters, 502 measuring current, 502 measuring high voltage, 501 diagram of connections, 501 measuring resistance, 503 Poundal definition, 13 foot, 14 Power alternating current, 281 average, 283 C. G. S. unit, 15 curve with E. M. F. and cur- rent, 282 examples, 16, 29 factor, 284 practical unit, 16, 24 Pressboard use, 52 Primary cell, 56 spiral, De Forest wireless tele- phone, 607 Principles alternating currents, 267 operation, Leonard system, 256, 257 wireless telegraphy, 544 telephony, 595 Problems alternating currents. 310 counter E. M. F., 100 divided circuits, 107 generators, 219 grouping of cells, 69 heat and resistance, 42 motors, 263 Ohm's law, 96 resistance, 42 shunts and com p. resistazices, 106 simple circuits, 91, 92 Index 633 Projectors search-lights, 395 Quantity C. G. S. unit. 18 practical unit, 18 relation to potential and ca- pacity, 278 Seactance, 546 alternating current, 277 Heactioos armature, 185 Heceiyer wireless telephone, 599, 608 Audion voltage, 608 battery B, 608 tuning, 609 Seceivers, telephones, 525 Bell, 526 bipolar, 526 watch-case, 527 Hed lead, 78 Regulation search-light arcs, 386 secondary cells, 84 series generators, 193 shunt generators, 199 fielay telephone switchboards cut-out, 536 line, 536 supervisory, 537 fieluctance definition, 138 speed regulation, 261 Remanence, 141 Semedies generators and motors, 504- 508 secondary cells, 87 Representation ^alternating currents, 275 Resin table of Insulators, 51 Resistance armature by comparison of de- flections, 327 instructions for test, 328 armature control of motors, 242 changes due to heat, 341, 342, 343 compensating, 105, 106 problems, 106 contacts, imperfect, 49 curve with time, 329 dead, search-lights, 387, 388 electromagnetic unit, 23 field windings, series, 329 joints, 49 laws, 36 parallel, 44, 47, 101 practical unit, 24 primary cells, 60, 61 problems, 42 problems on heat, 43 relation to heat, 38 series, 44, 47 series and parallel circuits, 47 shunt windings, 329 specific, 36 standard, 470 table, 38 temperature coefficient, 40 variation with temperature, 39 windings, in tests, 326 working battery, 61, 62 Resistance, arc lights arc, 384 apparent, 384 ohmic, 384 calculation dead resistance, 388 dead resistance, 387, 388 Resistance coils service testing set, 436 testing set, 434 winding, 434 Resistance, insulation dynamo, machines, 339, 482, 483 measurement, 480 634 Index Resistance, insulation— Cont'd direct deflection, 481 ohmmeter, 487 testing set, 487 voltmeter, 484, 485 example, 486 Resistance, measurement ammeter and voltmeter, 468 precautions, 468 armature. 490 battery, by testing set, 476 contact, 491 insulation, 480 fall of potential, 483 machine, 482 ohmmeter, 487 magneto, 479 potentiometer, 503 series windings, 489 connections, 489 shunt windings, 488 bridge, 488 voltmeter and ammeter, 488 testing set, 473 example, 474 voltmeter and standard resist- ance, 469 voltmeter, of, 468 voltmeter, with, 469 Resistances and shunts, 428 ammeter connections, 430 example, 429 millivoltmeters, 430 voltmeter connections, 428 Resonance alternating current circuits, 303 Retentivity, 141 Reversal currents, due to induction, 156 magnetism, 141 secondary cells, 77 Rheostatic control of motors, 254 series, 254 shunt, 255 Rotary converters description, 318, 319 diagram, 319 phase currents, 320 relation of voltages, 320 wireless sets, 320, 321 Rubber table of insulators, 51 uses, 51 Rules current direction, 125 hand, 126 polarity, 130 Sal ammoniac solution, 72 Sangamo meter, 459 ampere hour meters, 463 diagram of connections, 464 light-load compensation.. 463 operation with shunts, 462 sectional view, 460 speed adjustments, 462 switchboard meter, 461 Search-light arc, regulation, 385, 386 dead resistance action of. 387 calculation of, 388 lamp, 389 Search-light electric control adjustment, 415 assembly of training mechan- ism, 409 commutating device, 404 connections, 413 controller, 411 developed view of magnet coils and poles, 405 lamp, 412 operation, 414 sectional view of magnets and pole pieces. 406 sectional view of coils and poles, 407 table of polarity of pole pieces, 408 training system, 404 Index 635 Sechomineter measurement of inductance, 494 diagram of connections, 495, 496 Second C. G. S. unit of time, 10 Secondary batteries, 75 types, 82 spiral, De Forest wireless tele- phone, 607 Section secondary cells, 77 Selenium crystalline, 596 Self-induction, 546 alternating currents, 270 coefficient, 153, 272 curves of current, 271 effect, 270 E. M. F., 272, 273 measurement by B. G. W. wave meter, 593 wave meter. Type E. G. W., 589 Senders wireless telegrapy, 550. 551 Sending circuits wireless telegraphy closed, Donitz wave meter, 581 Fleming wave meter, 582 Pierce wave meter, 582 Slaby wave meter, 582 Separately excited generator, 190, 191 comparison of terminal volt- age, 204 Series charging, secondary batteries, 84 connecting machines in paral- lel, 227 Series-— Cont'd generator, 190, 191, 192 characteristic curve, 195, 330 comparison of terminal volt- age, 204 dynamo equations, 215 regulation, 193 grouping of cells, 63 motors, 243 control, 253 reversing, 254 starting, 254 stopping, 254 generators, 246, 247 resistance, 47 winding, measurement resist- ance, 489 connections, 489 Series-circuits alternating - currents, 286 example, 290 vector diagram, 298 Series and parallel circuits alternating currents, 296 diagram of connections, 296 vector diagram, 297, 298 Series connections telephone, 529 Series generator, 190, 191, 192 characteristic curves, 195, 330 connections, external circuit, 330 instructions, 330 total circuit, 331 Set, testing, 435 earth test, 478 keys, 477 use, 477 plugs, 474 uses, 472 checking ammeter, 477 checking voltmeter, 476 comparing E. M. F. of cells, 475 measuring resistance, 473 example, 474 measuring battery resist- ance, 476 measuring very low resist- ance, 474 636 Index Shapes incandescent lamps, 374 Shaping filaments, incandescent lamps, 367 Shellac table of Insulators, 51 use, 52 Short circuit armature, 512 external circuit, 509 field, 513 locate, electric fault finder, 518, 519 Shunt ampere connections, 427 explanation, 426 connecting machines in paral- lel, 225 current multiplier, 106 generator, 197, 198 characteristic curves, 199, 200, 332 comparison of terminal volt- age, 204 dynamo equations, 215 regulation, 199 motors, 240 control, 252 reversing, 254 starting, 264 stopping, 254 generators,. 245, 246 Shunts problems, 106 Shunt generator, characteristic connections connections instructions instructions 197, 198 curves, 332 for external, 333 for internal. 332 for external, 333 for internal, 334 Shunt windings resistance, measurement, 488 bridge, 488 voltmeter and ammeter, 488 Siemen's dynamometer, 418 Silks table of insulators, 51 Silver diamagnetic, 121 electrochemical series, 54 melting point, 39 resistance, annealed, 38 hard drawn, 38 specific, 37 table of conductors, 34 Silver chloride cell testing set, 435 Sines curve, 167. 269 properties, 168 Slaby wave meter description, 576 tuning closed sending circuit, 582 tuning open sending circuit, 583 Solenoid magnetic circuit, double, 136 magnetizing force, 132 stopped, 136 Sparking brushes, 326 limiting generator output, 212 Specific conductivity, 46 resistance, 36 table, 37 Specific gravity secondary cells, 82 effect on E. M. determination E. M. F. around armature, 360 Time C. O. S. unit, 10 Tin electrochemical series, 54 melting point, 39 Torque definition, 235 expression, 236 relation to speed, 238 Training system search-light electric 404 mechanism, 409 control. Transformers alternating current, 305 ratio of voltage and current, 307 continuous current, 312 efficiency, 308 losses, 308 oscillation, 551 principle, 158 vector diagram, 309 Transmitters telephone carbon, 523 Blake, 523 White, 524 Edison, 522 Hughes microphone, 522 Hunning, 522 Tune, tuning closed sending circuit Donitz wave meter, 581 Fleming's wave meter, 582 Pierce's wave meter, 582 Slaby's wave meter, 582 open sending circuit Donitz wave meter. 583 Fleming's wave meter. 583 Pierce's wave meter, 583 Slaby's wave meter, 583 Index 639 Tune, tuning— Cont'd receiving circuit Donitz wave meter, 586 Pierce wave meter, 585 wireless telephone, De Forest instructions, 602 receiver, 609 antennae, 610 earth lead, 610 pancake tuner, 609 transmitter condenser, 607 listening, 607 microphone, 607 primary spiral, 607 secondary spiral, 507 talking, 607 Tungsten filaments, 380 Undemmning generators, 372 Unit, units acceleration, 10 area, 10 candle-power, 371 C. G. S. capacity, 31 current, 17 E. M. F., 22 length, 10 mass, 10 power, 24 quantity, 18 time, 10 conductivity, 46 derived mechanical, 10 area, 10 velocity, 10 volume, 10 electrical heat, 26 electromagnetic resistance, 23 B. M. F., 18 force, 12 international, 31 magnetic field, 17 magnetic pole, 16 metric length. 9 mass, 9 time, 10 practical, 10 mercury Unit, units — Cont'd capacity, 32 current, 18 B. M. F., 22 power, 24 quantity, 18 work, 26 Vapor lamps mercury, 400 (see vapor lamps) Varnish table pf insulators, 51 Vector diagrams alternating current, 291 component and resultant E. M. F.. 274 E. M. F. parallel circuits, 300 resistance and inductive re- actance, 286 resistance and condenslve re- actance, 286 resistance and combined in- ductive and condenslve re- actance, 287 series circuit, 289 series and parallel circuits, 297, 298 transformer, 309 Volt, volts lost, 195 milli. 22 practical unit of E. M. F., 22 Volta, 22 Voltage arc lamps, closed, 385 open, 385 audion, 608 comparison compound generator, 205 separately excited generator, 204 series generator, 204 shunt generator, 205 measuring high by poten- tiometer, 501 regulation discharge second- ary cells, 84 relation continuous and al- ternating currents, 284 640 Index Voltmeter, yoltmeterj calibration, 471 connections, 471 care in connecting, 422 care in using, 422 checking by testing set, 476 decreasing range, 472 increasing range, 472 measuring current. 466 insulation resistance, 484, 485 connections, 484 example, 486 resistance, 467 of, 468 series winding, 489 shunt windings, 488 standard resistance, 469 with ammeter, 468 Weston, 680 description, 680, 681, 682 Volume C. G. S. unit, 10 Vulcabeston use, 52 Ward-Leonard motor control, 256 Water diamagnetic. 122 table of conductors, 34 Watt, watts apparent, 283 converting to B. T. U. per sec., 28 ergs per sec, 26 ft.-lbs. per min., 26 horsepower, 26 joules per sec., 28 kilogr. meters per sec., 26 curve, 282 practical unit of power, 24 relation to horsepower, 26 power factor, 284 true, 284 Watt hours secondary cells, 82 Wattmeters, 458 indicating, 459 recording, 459 Sangamo, 459 (see Sangamo meter) watt hour, 459 Waves electromagnetic, 555 analogy to soimd waves, 558 applied to wireless tele- phones, 599 form, 556 length, 556 meters, 575 properties, 556, 557, 558 relation of frequency and wave length, 557 Wave length measurement by E. G. W. meter, 591 (see wave meters, 575) Wave meters, 575 Wave meter, Type E. G. W. buzzer and battery, 590 condenser, 588 description, 587 diagram of connections, 589 employment, 590 determination of capacity, 593 measurement coeff. of selt- induction, 593 measurement degree of coup- ling, 594 measurement wave length, 594 measuring sensitiveness of detectors. 593 testing transmitter tone, 592 tuning circuits, 590 antenna, 591 diagram of connections. 592 closed receiving circuit, 591 helium tube, 591 receiving antenna, 592 diagr&m of connections, 592 telephone and detector, 591 wave measurement, 591 Index 641 Wave meter, Type E. G. W.— Cont'd helium tube, 590 hot-wire ammeter, 590 self-induction, 589 telephone, 590 Weight definition, 13 Weston ammeters, 425 portable, 426 voltmeters, 423 description, 423, 424, 425 Wheatstone bridge theoretical bridge, 432 White telephone transmitter, 524 Windings breaks, leaks or grounds, tests for, 479 fracture, 515 resistance of generator, 488 resistance of, tests, 460 Wireless sets rotary converters, 320, 321 Wireless telegraphy equation, 548 principles, 544 Wireless telephony De Forest system, 601 principles, 595 theoretical principles, 596 Wood table of partial conductors, 34 Wool table of insulators, 51 Work C. G. S. unit, 13 examples, 15, 29 practical unit, 26 Zinc constituent German silver, 36 diamagnetic, 122 electrochemical series, 54 resistance, pressed, 38 table of conductors, 34 use, 35 A'lDAIbAlDDl B89089681001A This book may be kept FOURTEEN DAYS A fine of TWO CENTS wiU becharged for each day the book is kept overtime. No. <91-B 0IMCO< l,^" y' /;. 