Electric Machines Mega Quiz 20

A 220 V D.C. generator is run at full speed without any excitation. The open circuit voltage will be

In a separately excited generator supplying rated load the armature reaction

If residual magnetism is present in a D.C. generator, the induced e.m.f. at zero speed will be

Armature reaction in a generator results in

Following energized winding of a D.C. machine should not be opened as it would produce high inductive voltage which may be dangerous to personnel and may cause its own insulation failure.