Power System Protective Relays: Principles & Practices

A relay that functions to prevent overheating of the field excitation winding by reducing or interrupting the excitation of the shunt field. See also: relay. (IA/ICTL/IAC) [60] field relay (power system device function numbers) A relay that functions on a given or abnormally low value or failure of machine field current, or on an excessive value

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