Ground fault circuit interrupter. GFCI protection can be provided by receptacles or breakers, and they must be installed in a readily accessible location so you can reach them if they trip.

Look for two buttons, labeled TEST and RESET, on the face of the GFCI receptacle. “It is easy to check if GFCI outlets have ...

See? Good and evil. An RCD (or GFCI in the States) is a kind of circuit breaker that trips when the amount of current in the hot and neutral mains power lines aren’t equal and opposite ...