40 PROBLEMS IN ALTERNATING CURRENT MACHINERY 



What is the regulation for an inductive load of 500 amperes 

 at 0.8 power factor? 



60. A 3-phase, Y-connected alternating-current generator is 

 rated to deliver 1640 kv.-a. at 13,500 volts. The armature has 

 an effective resistance of 1.52 ohms per phase and a synchronous 

 reactance of 37.4 ohms per phase. 



(a) What is the regulation of this alternator on an inductive 

 load taking 1500 kw. at 0.85 power factor? 



(b) What is the regulation on a condensive load taking 1500 

 kw. at 0.85 power factor? 



61. A 2-phase alternating-current generator is rated to deliver 

 3500 kw. at 10,000 volts. The armature has an effective resist- 

 ance of 0.64 ohm per phase and a synchronous reactance of 23.7 

 ohms per phase. 



(a) What is the regulation of this alternator on a non-induc- 

 tive load taking the rated kv.-a. ? 



(b) What is the regulation on an inductive load taking the 

 rated kv.-a. at zero power factor? 



(c) What is the regulation on a condensive load taking the 

 rated kv.-a. at zero power factor? 



62. A 760-kv.-a, 2200-volt, 3-phase alternating-current gen- 

 erator has an effective armature resistance of 0.17 ohm per phase. 

 The armature winding is connected in Y. With the armature 

 short-circuited the armature current is 338 amperes when the 

 field current is 60 amperes. The open-circuit characteristic 

 data are: 



