396 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



(19° 37') as indicated in Figure 10. The Pr vector Kr then follows, 

 90° of power phase or 45° of current phase, behind the current at re- 

 lease. The vector Kff, or undamped reactive power vector, Figure 13, 

 starts in phase with the current. 



-X- 





Figure 13. Rotative vector power diagram for p. d. standard phase and 

 for current standard phase. 



The stationary vector-diagrams of Figure 7 may be understood as 

 involving the following phase relations, with respect to the phase of the 

 undamped vector p. d. C/q, Figure 8. 



To = C^o^\^ = ^^ V2 \^ = UoCWfj \^ max. cyclic amperes (22) 



Pm = f/"/ \0 = ^^^^ \^ = ^ Y\4> max. cyclic watts (23) 



2 *> 



