Residual Current Device. Protects the user against short circuit (earth faults) and earth leakage caused by damaged cable or faulty equipment. A RCBO is a combined MCB and RCD, protecting against earth leakage/short circuit and overload.
Residual Current Device. A type of fuse which monitors the flow of electrical current through the live and neutral wires of a circuit. When an RCD detects an imbalance caused by earth leakage, it cuts off the supply of electricity as a safety measure.
Residual Current Device. A safety device (a modified circuit breaker), usually installed within a distribution board which monitors the circuit that is is serving. In the event of a earth fault or "earth leakage" contacts will open and the supply will be isolated. Used to enhance protection where the adequacy of the earth return path may be suspect.