MCB & RCCB Selector
Get a starting point for a circuit’s protection: a suggested MCB current rating and trip curve, the minimum cable that matches it, and the RCCB sensitivity for shock protection. Remember the golden rule: the breaker protects the cable, so the two are always chosen as a matched pair — this tool is an aid, and a licensed electrician makes the final selection.
Circuit draws ~7.8 A (1-phase).
The golden rule: load current ≤ MCB rating ≤ cable capacity. The MCB must never be larger than the cable can carry — a bigger breaker “to stop tripping” removes the cable’s protection.
Indicative only. This suggests a starting MCB rating from the load current and a trip curve from the load type, plus the minimum matching copper cable. It does not model cable length (voltage drop), grouping, ambient temperature, breaking capacity or discrimination. The breaker, cable and RCCB must be selected and coordinated by a licensed electrician to IS 732 and IS/IEC 60898. Never change a breaker yourself.
Related Guides — Deep-dive reading
Choosing the Right MCB Rating for Each Circuit
How the correct MCB is chosen — sized to protect the cable, above the circuit's normal load, with the right trip curve for the appliance. The common ratings for lighting, sockets, geysers, ACs and kitchens, and the golden rule that ties the breaker to the wire.
Electrical & WiringRCCB, RCBO & ELCB: The Devices That Protect You From Shock
The single most important safety device in a home distribution board — the residual current device that detects electricity leaking to earth and cuts power in milliseconds. What RCCB, RCBO and ELCB mean, why 30 mA matters, the difference from an MCB, and why every home must have one.
Electrical & WiringMCB vs MCCB: What They Do & Which Your Home Needs
The two circuit breakers that protect wiring from overload and short circuit — the MCB in every home distribution board and the larger MCCB in bigger installations. What each does, the trip curves and ratings, when you need which, and why a bigger breaker is never the fix for tripping.
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