What is the function of earthfault relay?

Answer Posted / micro power system, bangalore.

Actually earth fault relay's function is,it calculates the
vector sum of all the three currents flowing in R Y B
lines. If the vector sum is not zero then there is a fault
current flowing in particular line. since these lines are
connected to load say generator then, more than the rated
value of current flowing through windings ,hence windings
will damage so to prevent these type of damages EFR is
used.
if any comments pls send to shreeshara@gmail.com

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