Answer Posted / athar abid

As we Know that

KVA = Sqrt 3 . Voltage(V) . Current(I)

Now for 400V (Phase-Phase) syayem

I = 500KVA/(1.732 * 400)
=500*1000/(1.732*400)
=721.7 Amps

There is no standard breaker available with this rating, so
take one step above rating i.e. 800Amps

Hope its clear.

Regards
Athar Abid

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