What is the difference between REF relay and Differential protection relay

Question

Accepted Answer

REF relay is used for earth fault protection while differential protection relay is used for detecting internal faults.

REF relay is used to detect earth faults in electrical systems.
Differential protection relay is used to detect internal faults within electrical equipment.
REF relay compares the current flowing into and out of the system to detect any imbalance caused by earth faults.
Differential protection relay compares the current entering and leaving the equipment to detect any difference, indicating an internal fault.
REF relay is commonly used in power distribution systems to protect against ground faults.
Differential protection relay is commonly used in transformers, generators, and motors to protect against internal faults.

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