Overview
The EZ9R34263 is a Schneider Easy9 2-pole residual current circuit breaker (RCCB) rated for 63 A continuous load with a 30 mA earth-leakage sensitivity, built to IEC 61008-1 for Type AC waveforms. Its 630 A rated breaking and making capacity gives short-circuit withstand headroom well above the 63 A continuous rating, so it holds coordination in a residential or small commercial distribution board without nuisance tripping on upstream faults.
How it compares
The closest functional alternate is the EZ9R34240: same 2-pole, same 30 mA sensitivity, but rated 40 A instead of 63 A. The EZ9R34263 handles a heavier continuous load; swap only if the downstream circuit is sized for 63 A.