WHY IS RESTRICTED EARTH FUALT PROTECTION NEEDED?? WHY CANT
DEIFFERENTIAL PROTECTION SUFFICE???

Answer Posted / ram niveth

REF is a backup protection for transformer incipient
faults.
if differential fails REF comes on line.
if both protections are used , usually REF time setting
will be less than differential setting

Is This Answer Correct ?    15 Yes 27 No



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