A 3-phase, 4-pole, 50 Hz induction motor is uses DOL method of starting. It is later replaced by auto transformer method of starting with a tapping ratio of ‘x’, then the starting current reduces by?(a) x(b) x^2(c) 1/x(d) no change in the starting currentThis question was addressed to me in an internship interview.This is a very interesting question from Starting of Polyphase Induction Motors-I topic in portion Starting of Induction Motors of Electrical Machines

A 3-phase, 4-pole, 50 Hz induction motor is uses DOL method of startin

1.	A 3-phase, 4-pole, 50 Hz induction motor is uses DOL method of starting. It is later replaced by auto transformer method of starting with a tapping ratio of ‘x’, then the starting current reduces by?(a) x(b) x^2(c) 1/x(d) no change in the starting currentThis question was addressed to me in an internship interview.This is a very interesting question from Starting of Polyphase Induction Motors-I topic in portion Starting of Induction Motors of Electrical Machines
Answer» The correct option is (B) x^2 The best I can EXPLAIN: The STARTING current reduces by a fraction of x^2.

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