A piece of equipment that can detect certain faults in an electrical system when it is in operation and which responds to these by switching the system off. Residual current devices can be incorporated into the main switchboard of the system or...

A residual current device (RCD), or residual current circuit breaker (RCCB), is an electrical wiring device that disconnects a circuit whenever it detects that the flow of current is not balanced between the phase ("hot") conductor and the neutral...