circuit breaker distribution transformer density sensor

Residual-current device - Wikipedia residual-current device (RCD), residual-current circuit breaker (RCCB), or ground-fault circuit interrupter (GFCI) is a device that quickly breaks an electrical circuit to prevent serious harm from an ongoing electric shock. Injury may still occur in some cases, for example if a human falls after receiving a shock, or if the person touches both conductors at the same time which an RCD won't ...