Why is the earth fault relay connected to the Yellow
Phase?

Answer Posted / k.prakashchandra

Earth fault relay is not connected any phase.The balancing
current is made to pass through this relay.In two EFR and
one EFR protection scheme,OCR s are usually provided on R
and B phases ,which makes one assume that the EFR is
provided on Y phase.You can have 3 OCR and 1 EFR protection
scheme also

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