What's ND relay & it's functions?

Answer Posted / raj

IT IS NEUTRAL DISPLACEMENT RELAY AND IT IS USED FOR VARIOUS
PROTECTION BUT THE PRINCIPLE IS THAT IN CASE OF NO FAULT NO
VOLTAGE IN RELAY ( IT USED OPEN DELTA VOLTAGE FOR RELAY
INPUT ) AND IF FAULT OCCUR IN ANY PHASE THEN UNBALANCED
VOLTAGE WILL GET ACROSS OPEN DELTA FOR RELAY TO OPERATE.

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