Question

In case of a power transformer, the no load current in terms of rated correct is?

(a) 10-20%

(b) 2-6%

(c) 15-20%

(d) 30-50%

This question was addressed to me during an interview.

This interesting question is from Transformer Phasor Diagram in section Transformers of Electrical Machines

Answer 1

The correct answer is (b) 2-6%

The best explanation: The air gap is very less in the transformer, so the magnetizing current needed is around 2-6% only.