For phase to ground faults, resistive reach should be set to give maximum coverage considering fault resistance, arc resistance & tower footing resistance. It has been considered that ground fault would not be responsive to line loading.
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In case of phase to phase
fault, resistive reach should be set to provide coverage against all types of anticipated phase to
phase faults
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In relays having quadrilateral
characteristics, it shall have independent resistive
reach settings for Phase to ground faults, and Phase to phase faults,
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While setting resistive reach load encroachment possibility shall be considered.