FAULT DETECTION

摘要

Apparatus for the detection of leakage current in a system includes a power supply (800) and conductors from the supply for supplying power to a load (813) connected to the system. There is an interrupter (806) connected in the system and to a ground point (807) such that a ground leakage current in the system has a closed circuit. Activation of the interrupter every 12 seconds effectively generates a pulse interrupted ground fault signal. Such signal is detected by a magnetic sensor (25) located relative to a multi-feeder system with high capacitive reactance (810). The sensor is immune to random electromagnetic and electrostatic conditions in the distribution system. The sensor (25) is synchronized to operate with the interrupter (806) so that sensing is effected at a steady level of a square wave interrupted pulse.