Answer / vishal

differential relay operates when the phasor difference of two or more electrical quty exceeds a pre determined limit.
in case of power transformers the vectors compared are the current entering and leaving the winding
..if the current entering is more ,indication of fault and relay operates

Answer / vasim

CT connections from primary side & secondary side are
connected together in the differential relay if there is
any difference current or fault current flows there above
the preset time & value of current than the relay operates.

Answer / ashutosh

in differential relay we use to the differential principle
means in it we compare to the similar actuating Quantity.
Differential relays are used to determine the inter turn
Fault

Answer / harish kumar

Differential relay will operate with differential current between phase and neautral of the generator. it is operated with CT CONNECTIONS

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