What is stall fault in EOCR for 3-phase Ac induction motor?

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In AC induction motor when we start it, at starting it will take 5-7 times of motor rated current and it should come down in 4-5 second and will take no load current 40% - 50% of motor rated current.

Then we can now give it on load.

Now suppose if there is jam in mechanical coupling side, motor shaft then what would happen.

In this case if we start the motor then it take it's starting current 5-6 times of rated current and because it is jam either from mechanical coupling,gearbox or motor shaft problem 

Motor can't start rotating and motor will take  current 5-6 times and  will not come down to it no load current as the delay time of EOCR end it will trip in stall fault.

So if it trip in stall fault then it is mechanically stuck up, it happens at start.



If any queries then do comment.

Regards.







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