330 



ELEMENTS OF ELECTRICAL ENGINEERING. 



current three-phase feeder panels (A.T.F. 2,300 V. 75 Amp.). 

 The figure shows also the connections of a 3OO-kilowatt, three- 

 phase synchronous motor (2 A TY 2,300 V. 300 K.W.), and the 

 connections of a 3OO-kilowatt six-phase rotary converter (AHR 

 2,300 V. 300 K.W.) with its step-down transformer and syn- 

 chronizing receptacle. 



The " TA regulator" which is indicated in Fig. 280 is an 

 accessory of the generator (ATG 2,300 V. 1,000 K.W.). The 



connections of the " TA regulator" 

 are not fully shown in Fig. 280 

 but they are described in detail in 

 Art. 155. The oscillating armature 

 of the voltage regulator short-cir- 

 cuits a resistance, as explained in 

 Art. 155* This resistance maybe 

 inserted permanently either in cir- 

 cuit with the field winding of the 

 exciter or in circuit with the field 

 winding of the alternating-current 

 jj m generator. This resistance is marked 



"II [\ff "equalizer rheostat for TA regu- 



M later" in Fig. 280. 



The device on each feeder panel 

 marked "relay" in Fig. 280 serves 

 to control the time which elapses 

 between the instant of an overload 

 or short-circuit on the pair of feeders 

 and . the instant of tripping of the 

 circuit-breaker. 



The essential features of the ground detector which is shown 

 in Fig. 280 are described in Art. 153. The dial synchronizer, or 

 synchronism indicator, which is shown in Figs. 279 and 280, is 

 described in Art 151. 



149. Switchboards for receiving stations, (a) Induction motor 

 panels. Small induction motors are generally provided with a 



Induction Motor Panel. 

 Fig. 281. 



