104 THE DESIGN OF STATIC TRANSFORMERS 



phase ami magnitude by the vector A B, and is seen to be 

 equal to 129 volts when, as in Fig. 61, G is equal to 0,886. 

 In Fig. 62 we arrive at the value of G corresponding to the 



FIG. 63. Transformer diagram 

 wit h 30 per cent, reactance 

 drop and 15 per cent. I R 



dr. .p. Angle of lag </> = 78. 

 Cos $ = 0.21. 



FIG. 64. Transformer diagram 

 with 30 per cent, react- 

 ance drop and 1T> per cent. 

 / // drop. Anglo of lag 

 <J> = 90. Cos d> = 0. 



maximum drop. This always occurs when the tangent of the 

 angle of lag of the secondary current behind the secondary 

 pressure is equal to the ratio of the reactance drop to the 

 resistance drop, i.e., for the condition 



BE : C E = C D:AD. 



