MCB, RCCB or RCBO: which protection your home needs

An MCB (miniature circuit breaker) protects the wiring from overload and short circuit — it trips when too much current flows. It does nothing to protect a person from an electric shock.

An RCCB (residual current circuit breaker) does the opposite: it watches for current leaking to earth — through a person or a fault — and disconnects fast enough to save a life. It does not protect against overload.

An RCBO combines both in one device: overload and short-circuit protection plus earth-leakage protection, per circuit. Fitting an RCBO on each circuit means one faulty appliance trips only its own circuit, instead of an RCCB taking out the whole house.

For a modern home, we usually recommend MCBs plus a single RCCB per section as the economical option, or RCBOs per circuit where uninterrupted supply to the rest of the home matters.

RCCBs come in sensitivities — 30 mA for shock protection on socket and wet-area circuits, 100–300 mA for fire protection on sub-mains. Using the wrong sensitivity either fails to protect or nuisance-trips constantly.

Bring us your circuit list and we will specify the board, the MCB curves and the RCCB type for your actual loads — genuine Legrand, Schneider, Havells, ABB or L&T, with warranty intact.