POLYPHASE SYSTEMS AND POWER 77 



39. Repeat problem 38, except that the wattmeters are in the 

 same branches as circuits (b) and (c). (10 ram.) 



40. Determine graphically what the readings on two watt- 

 meters placed with their series coils in the leads between the first 

 and second and between the second and third circuits of problem 

 33 would be. (10 ram.) 



41. A 3-phase, delta-connected alternator is giving 750 amperes 

 for one phase only. What will be the current in each circuit of 

 the alternator? Also what if a 200-ampere, single-phase circuit 

 is connected to each of two phases? (5 ram.) 



42. Show what, on a basis of heating, will be the capacity of 

 a 100-kilovolt-ampere, 3-phase delta-connected alternator when 

 run single phase. Also if the alternator is Y-connected. (2 ram.) 



43. Repeat problem 42, except that the load is to be two equal 

 single-phase circuits, one on each of two phases. (3 ram.) 



