Hi ,what the accurate method to set correct(In) over load to protect the 3~ mot

Hi ,what the accurate method to set correct(In) over load to
protect the 3~ motor

Question Posted / obeidamakk

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Hi ,what the accurate method to set correct(In) over load to protect the 3~ motor..

I follow this method where before setting the overload
current setting I carry out an actual current consumption
test with a clamp ammeter.If the reading is lower than the
rated full load current of the motor I would set it at
actual reading add 5 percent and set it as the tripping
current. But if the the actual consumption is already the
rated fl current or almost it than the setting would be at
the rated full load current of the motor but never exceed
it.This way if it trips at any time than find out the root
cause and than only put into operation.

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Hi ,what the accurate method to set correct(In) over load to protect the 3~ motor..

Answer / joseph

The correct setting of over load relay is 105% of full load current.

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Hi ,what the accurate method to set correct(In) over load to protect the 3~ motor..

Answer / pundlik wanwe

For calculation of thermal over load current setting following formula is used
OLR = Motor FL current/ CT Ratio X 105%
Normally it is set at 105 %

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Hi ,what the accurate method to set correct(In) over load to protect the 3~ motor..

Answer / simon peter

Firstly u should know the correct ampere of the load which will b drawn. According to rating buy ELCB,M.C.B of that rating .....

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