Answer / ashif khan

before the selection,first we should know that it is single
phase or three phase load.in case 1-phase we use p=vicosф to
find out the load current but in 3-phase we use p=√3vicosф.
suppose it's 3-phase then load current=382amp.now add
minimum 25% safety factor to it.then it will be 475amp ,so
we can select C.B of 500amp current rating.

Answer / velusamy

Select based upon current rating
next 220kw using voltage

For Ex:
220kw
415v
means it will take arround 350 Amps so we can select the CB

more than the current with withstand capacity

Answer / sennapparajan

for 220kw load curent is 380 amps. so your breaker should
be min 1.5 times of full load current. so u can select 630A
breaker.

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