The Schneider Electric A9KR14425BQ is a 4-pole residual current circuit breaker (RCCB) from the Acti9 ID K series, rated 25 A with 300 mA earth-leakage sensitivity. The tripping mechanism is voltage-independent, so it clears a ground fault even if the supply neutral is lost, which matters for group incomer positions where the RCCB sits ahead of the branch MCBs.
Breaking and making capacity is listed as Idm 500 A / Im 500 A — this is the short-circuit withstand capability of the RCCB itself; it expects an upstream overcurrent device (MCB or fuse) to clear high faults, while the RCCB handles the earth-leakage interruption. The 300 mA sensitivity is a delayed-action threshold used for fire protection or for circuits where nuisance tripping from normal leakage (long cable runs, industrial heaters) would be unacceptable. It is not suitable for personal shock protection — that requires 30 mA or lower. The instantaneous time delay means no intentional delay before trip, so it responds as fast as the voltage-independent mechanism allows.
The IP20 body is fine for enclosed distribution boards; an IP40 modular enclosure rating applies when installed in a standard consumer unit or panel.
Certified to IS 12640-1, EN/IEC 61008-1, and EN/IEC 61008-2-1. The 8/20 µs impulse withstand rating of 200 A per EN/IEC 61008-1 confirms it can handle surge currents from lightning or switching without nuisance tripping.