416 



INDEX 



N 



Neutral current in three-wire gene- 

 rator, 391. 



No-load power factor of transformer, 

 291. 



N-phase converter, 376. 



Ohm definition, 75. 

 Ohm's law, 75. 



Open-circuit reactance of trans- 

 former, 297. 

 Open delta connection, 313. 



P 



Parallel operation of alternators, 281. 

 compound generators, 195. 

 shunt generators, 194. 



plate condenser, 19. 

 Permeability, 46. 

 Permeance, 48. 

 Phase characteristics of synchronous 



motor, 278. 



Polyphase armature reaction, 253. 

 Potential, electric, 6, 8-11. 



gradient in a lead-covered cable, 36. 

 special cases, 12-14. 



magnetic, 45. 

 Potentiometer, 85. 

 Power, 52. 



apparent, 117. 



factor, 118. 



in alternating-current circuits, 113. 



units of, 52. 

 Progressive winding, 153. 



R 



Rating of alternators, 250. 



rotary converters by armature 



heating, 383. 

 Ratios of e.m.fs. and currents in 



rotary converters, 376. 

 Reactance, 131. 

 armature, 176. 

 condensive, 108. 

 inductive, 104. 

 leakage, 295. 

 synchronous, 261. 

 transmission line, 398. 



Rectangular coordinates, 135. 

 Rectifier, mercury arc, 393. 

 Regulation of direct-current genera- 

 tor, 187. 



Regulator, induction, 320, 322. 

 Repulsion motor, 364. 

 Resistance, 76, 131. 

 commutation, 176. 

 effective, 131. 



effect of temperature on, 76. 

 leads in alternating-current series 



motor, 362. 

 of brush contact, 176. 

 conductors, 78. 

 insulators, 78. 



starting of induction motor, 344. 

 Resistivity, 76. 



temperature coefficient of, 77. 

 Retrogressive winding, 154. 

 Reversing direction of rotation of 



induction motors, 330. 

 Revolving m.m.f. and flux of stat -, 



328. 



Ring winding, 146. 

 Rotary converter, 369. 



starting, 388. 

 Rotating field in single-phase ir 



tion motor, 353. 

 Rotor efficiency, 339. 



magnetomotive force, 331. 



S 

 Saturation curve, 161. 



calculation of, 163. 

 Self-inductance, 90. 



effect on commutation, 1 " '. 

 in direct-current circuit 

 Separately-excited generate .37. 

 Series-drum windings, 151. 

 field loss, 211. 

 generator, 193. 

 motor, 200. 

 transformer, 315. 

 Short-pitch winding, 246. 

 Shunt-field loss, 210. 

 generator, 188. 

 motor, 199. 

 Sine wave of e.m.f. and current, 99. 



