Answer / a.p.nanjappa

Load current is 300A. The equipment shall withstand the
starting current -which is around -5-8xIn.It is preferable
to select 1ooo-1200A/1A OR 5A.
WE ADOPT THIS THUMB RULE for our protection setting& co-
ordination.

Answer / wareagle

600/5 would work nicely. One on each phase.

Answer / p_mehboobkhan

i want answer...

Answer / a.p.nanjappa

The neutral is a point in power transformer or in motor
connection where all phases are connected.In this point
voltage is zero. when you connect thisoint to earth, the
fault current or capacitance circulating current flows to
earth.
when a fault occurs , current is high.Therefore,CT ratio
should be 1000-1200/5 or 1A.

It is usually upto designer or protection device supplier.

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