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what is cogging and crawling
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Answer Posted / heramb mayadeo
when an induction motor refuses to start even if full
voltage is applied to it, this is called as cogging. this
happens when the rotor slots and stator slots are same in
number or they are integer multiples of each other. due to
this the opposite poles of stator and rotor ome in front of
each other and get loked.
on the other hand when an IM runs at a very low apeed
(precisely speaking 1/7th of synchronous speed)even if full
rated voltage is applied to it,then it is called at
crawling. this happens due to harmonic induction torques.
in which torques due to 7th harmonic overpower the driving
torque(fundamental component torque).
| Is This Answer Correct ? | 336 Yes | 18 No |
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