Answer / shailender gupta

Ans is right but required
calculation.is
p= root(3) VI COS phi.
find out current i.e I after
putting the value of V , p cosphi
and you will get required
current and multiply with 1.75
acc. to IEC fir safty purpose for
equipment

Answer / sanjeev singh

ACB generally refers to Air Circuit Breaker used for the protection of devices from overloadings or short circuit currents has its range upto 1600A.
MCCB generally refers to Moulded Case Circuit Breaker has its range from 15A to 1600 and generally start at 14kAIC but go up to 100kAIC for applications with high fault current capacity.

So essentially, an ACB is used as almost the last line of defense during a fault. ACB are designed to be field maintainable, unlike MCCBs which are not.

Answer / e.r k.k dash

Suppose there is 750 kva transformer.then acb can choosen by following foamula=kva*1.35=amp
750*1.35=1012.50 amp
So next higher range is chossen.that is 1250 4 pole with high breaking capacity.

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