Answer / prabhas

Motor current rating is calculated by using the formula
I= P/1.73*V*PF

Normany it is 1.8times of power of the motor will be their
in 420v 3 phase motor.

Ex: 500Kv HT motor 11kv voltage
is Approx. 32A is the rated current.
so 32.5 or 33A is OL Setting.

Answer / manish

=32*0.9
=28

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