The method used is called pilot earth loop or earth continuity monitoring where an additional core pilot cable is included with the power and earth cores in the trailing or reeling cables which supply power to the machines.
Earth continuity relay.
We took a fresh look at earth continuity safety and as nzs2081 compliance to design a new method of earth continuity protection that utilises a trip curve to discriminate between earth disconnection faults and incremental increases in the earth return impedance.
Earth continuity failure protection.
The bramco ic3 earth continuity relay is designed to actively monitor the resistance of the pilot earth cir cuit in a supply cable by diode termination.
The ic3 utilises microprocessor technology to provide a greater level of stability over longer pilot cables by using digital filtering techniques.
As such the operating relay and the contactor will therefore open.
Due to a fault in the distribution system or line or if the power to the area is switched off for any reason the supply to the transformer and thus to the pilot circuit will cease.
Ampcontrol remains at the top of the field for innovation in earth continuity protection relay design.