ALTERNATOR REGULATION AND OPERATION 



151 



cuited. There are two methods of connecting the ammeters in 

 tliis test. They may be connect CM! in V, Fig. 153 (6), in which 

 case the ammeters ivad the linr current directly, or they may be 

 connected in delta. Fig. l.">:-> (<), in which case the line current is 

 obtained by multiplying the ammeter readings by \/3 or 1.73. 

 With delta connection the ammeters need be only about half the 



Short- Circuit Test -Ammeters in Y 



(c) Short-Circuit Tett -Ammeters in Delta 



Flo. 163. ( M for nirikiiiK open- and 8iiort--irMiit tests of an ;ilt-- 



I 1.7:; or 0.58) necessary i' nl ' the F-oonnection. The 



: tlie ammHer iv;iliiiu- i> !i.-ually taken, although there 

 should be but little difference in the three readin. 



In c.-dculati! .LMilation of a t hre-ph:i>e alt ernat or, only 



onr of ii- three phases is con-ideivd when niakinu computations. 

 The reuulath 'UCy, etc.. of one phase is determined and 



the mad line being symmetrical, t In < ! her \ hase- will have similar 



