THE INDUCTION MOTOR. 



potential of the transformer be no volts. The resistance of the pri- 

 mary be 2 ohms. The semi-circle Ot can then easily be constructed. 



All that remains to be done is to construct the semi-cii*cle.for the con- 

 stant-potential transformer. Oi, Fig. 44, is a field equivalent to no volts. 

 O2 is a field equivalent to 31.5 volts; hence, if the potential is kept 



constant at no volts, X 5 = 174 amp. will flow through the 



DIAGRAM ILLUSTRATING METHOD OF 



RECIPROCAL VECTORS. 

 Angle 0^0 A,- Angle 4 O A, ; 

 Angle M'O'A,- Angle M A, ; 

 Angle L' A.- Angle L A, . 

 0~M . OM'- OD - 6~D'- OL . O~L 

 Fig. 43- 



transformer at the same phase-angle. We thus get point 2. The 

 centre of the semi-circle can at once be. found, points I and 2 being 

 determined, as angle Ot O A is equal to angle O A. 



150. The ordinates of the semi-circle Ot represent the watt-current 

 of the transformer, the ordinate of point I being equal to 5 2 X 2 -f- no 



80 



