what is cogging and crawling

Answer Posted / sunil parmar

cogging---the no. of stator slots is equal to the rotor
slots and due to 5th harmonic rotor fails to start and
causes magnetic locking this is called cogging....to
troubleshoot this scked rotor is used.and it require large
torque to overcome this strogr alignment

crawling---the speed of the motor is 7th time that of the
synchronous speed ie.Ns/7 is called as crawling

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