Answer / dinesh kumar

In earth fault protection the feeder or drive is protected
against an earth fault.In restricted earth fault protection
the complete winding of transformer or generator is not
protected against earth fault depending upon the value of
resistance connected in neutral grounding.If the earth
fault occure in the part of unprotected portion of winding
the eart fault relay will not trip

Answer / srinivas

earth fault protection allows the total fault current passes through the conductors, by this there may be chance of insulation breakdown, leads to machine failure.

restricted earth fault protection consists the resistance in the neutral wore that limits the fault current to certain level (it depends on the value of the resistance being added), there by more safety to the machine and auxiliaries.

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