GROUND FAULT RESPONSIVE PROTECTION SYSTEM

摘要

A multi-zone ground fault responsive protection system having three interlocked ground fault responsive subsystems each having a ground fault sensor, a circuit interrupter and an interrupter trip relay operable by the sensor for tripping the interrupter when the ground fault current reaches a predetermined adjustable actuator level. The subsystem relays are interlocked so that the downstream and intermediate subsystem relays are operable while activated to set the respective adjacent upstream subsystem in a time delay operating mode and also so that the downstream subsystem is operable while activated to disable the upstream system.