RCCB, RCBO and ELCB explained: how they differ, when to use a combined RCBO, and Type AC / A / F / B for modern loads.
Residual current devices save lives by cutting the circuit when current leaks to earth — but the three names cause more confusion than the technology. RCCB, RCBO and ELCB are related, and picking wrong leaves a circuit either unprotected or nuisance-tripping.
| Device | Does what | Needs a separate |
|---|---|---|
| RCCB (residual current circuit breaker) | Earth-leakage trip only | MCB for overcurrent |
| RCBO | Earth-leakage + overcurrent in one unit | Nothing |
| ELCB | Legacy earth-leakage (voltage or current sense) | MCB + proper earthing |
An RCCB protects against shock but does nothing for a short circuit, so it sits behind an MCB. An RCBO is the two functions in one module — the modern default for a final circuit.
The type states which leakage waveforms the device detects.
For anything with a rectifier, variable-speed drive or charger, specify at least Type A; for EV or solar, Type B.
ELEHPD RCBOs, RCCB/ELCB devices, MCBs and GFCIs cover AC through Type B duties for final and group protection.
An RCCB trips on earth leakage only and needs a separate MCB for overcurrent; an RCBO combines both functions in one module — the modern default for a final circuit.
Type A at minimum for anything with a rectifier or drive, and Type B for EV chargers, PV and VFD outputs where smooth DC leakage can occur. Type AC only covers pure sinusoidal leakage.
30 mA for shock protection on final circuits; higher ratings serve fire protection or selectivity where an upstream device requires it.
Send the ratings, dimensions and quantities you are working to and we will confirm the closest match from the ELEHPD catalogue, the compliance documents available for it and the lead time. OEM branding, private model numbering and buyer-specific cartons are available on qualified volumes.