ALTERNATOR - Quiz

1) What is the speed of an alternator connected with a supply frequency of 50 Hz at rated voltage having 4 poles?

1000 rpm 1500 rpm 3000 rpm 4500 rpm

2) What condition the two lamps become bright and one lamp dark during paralleling of two alternators?

Terminal voltages are equal Voltages and frequencies are equal Voltages and phase sequence are equal Both the alternators receive same frequency

3) What causes the terminal voltage of an alternator reduces, if the load increases?

Field resistance Armature reaction Inductive reactance Armature resistance

4) What is the purpose of using damper winding in AC generator?

Prevents heating Reduces copper loss Reduces windage loss Prevents the hunting effect

5) Calculate the speed in r.p.s of the 2 pole, 50Hz alternator?

50 rps 100 rps 1500 rps 3000 rps