A 4-pole, 3-phase, 50 Hz, slip-ring induction motor rotates at 1440 r.p.m. With slip-ring terminalsshort-circuited. The rotor resistance is 0.1 phase and standstill reactance/phase is 0.6 N. If anexternal resistance of 0.1 /phase is added to the rotor circuit, what will be the new full-loadspeed?Ans[ 1380 r.p.m.]

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A 4-pole, 3-phase, 50 Hz, slip-ring induction motor rotates at 1440 r.p.m. With slip-ring terminals short-circuited. The rotor resistance is 0.1 Q/phase and standstill reactance/phase is 0.6 2. If an external resistance of 0.1 Q/phase is added to the rotor circuit, what will be the new full-load speed? Ans[ 1380 r.p.m.]

A 4-pole, 3-phase, 50 Hz, slip-ring induction motor rotates at 1440 r.p.m. With slip-ring terminals short-circuited. The rotor resistance is 0.1 Q/phase and standstill reactance/phase is 0.6 2. If an external resistance of 0.1 Q/phase is added to the rotor circuit, what will be the new full-load speed? Ans[ 1380 r.p.m.]

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter35: Harmonics 916

Section: Chapter Questions

Problem 3RQ: Would a positive-rotating harmonic or a negative-rotating harmonic be more harmful to an induction...

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