INDEX 



365 



U 



Undercutting commutator mica, 181 

 UNDERBILL, C. R., referred to, 48 

 Units, conversion of centimeter to 

 inch, 2 



V 



Vector diagrams of alternator: 

 For determining inherent regula- 

 tion, 315 



Of short-circuited armature, 308 

 On lagging power factor, 289, 290, 



311, 334 



On zero power factor, 287, 307 

 Velocity of air in cooling ducts, 268, 



357 



peripheral (see Peripheral ve- 

 locity). 

 Ventilating fans, power necessary 



to drive, 107, 318 

 Ventilation of armatures, 105, 261, 



351 

 Virtual values of irregular waves, 



294, 346 



Voltage (see also E.m.f.). 

 drop at brush contact, 179 

 generated by cutting flux, 71 

 rise when switching current off 

 coil, 33 



Voltage,usual, of A.C. generators, 248 

 Voltages to be considered in connec- 

 tion with insulation problems, 33 



W 



WADDBLL, DR. J. A. L., referred to, 5 

 WALKER, PROP. M., referred to, 



107, 255 



Wave form (see E.m.f. wave form). 

 Wave winding (dynamos), 86 

 Wedge for rotor slots, 336 

 Whirling speed of rotors, 326 

 Windage, loss due to, 196, 317, 356 

 Winding, depth of, to give required 



excitation, 43 

 on magnet limbs, 55 

 shunt coils with two sizes of wire, 



43 



Windings (see Armature field, mag- 

 net, windings). 

 Wire (see also Copper wire), 

 enamelled, 38 

 tables, 34, 35 



Y connection, 244 



Yoke ring, dimensions of, 228 









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FACULTY OF APPLIED SCIENCE 



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Date.. 



