Question { Voltech, 6601 }

How to select Main CB Rating for 220 KW Load?

Answer

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.