Question

A 3-phase, 4-pole, 50 Hz induction motor is uses DOL method of starting. It is later replaced by reactance method of starting with a fraction of ‘x’, then the starting current reduces by?

(a) x

(b) x^2

(c) 1/x

(d) no change in the starting current

This question was addressed to me in a job interview.

Enquiry is from Starting of Polyphase Induction Motors-I topic in chapter Starting of Induction Motors of Electrical Machines

Answer 1

Right option is (a) x

To elaborate: The current will be reduced by a fraction of x.