Explain how you can give the overload setting to any Motor
Protection
Relay for a HT motors with formula and example?

Answer Posted / 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.

Is This Answer Correct ?    6 Yes 3 No



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