SYNCHRONOUS MACHINERY 



263 



In Figs. 240, 241 and 242 are drawn the diagrams for the three 

 cases (1) <j) = 0, or non-inductive load, (2) < = 60 lag, or induc- 

 tive load with a power factor of cos 60 = 50 per cent, and (3) 

 = 60 lead, or capacity load with a power factor of 50 per cent. 



FIG. 241. 



The relation between E , E and 7 can be expressed in the form 

 of an equation by reference to Fig. 243, which is a reproduction of 

 Fig. 239. 



= (E cos <f> + 7r) 2 + (E sin cf> + 7z ) 2 



or 



E Q = V(E cos <f> + 



(E sin <f> + 7z ) 2 . 



(255) 



