The Schneider Electric A9Z35263 is a 2-pole residual current circuit breaker (RCCB) from the Acti9 iID series, rated at 63 A continuous current with 300 mA earth-leakage sensitivity. That 300 mA threshold is sized for general distribution and submain protection where a 30 mA device would nuisance-trip on normal cable leakage — it's the standard choice for circuits feeding multiple socket outlets or fixed equipment where the shock-protection role is covered downstream by 30 mA RCDs. The Type A-SI (Super Immunised) designation means it handles pulsed DC fault currents from single-phase rectified loads (switch-mode supplies, LED drivers, VFDs) and is selectively time-delayed, so it coordinates with downstream 30 mA devices: a fault on a final subcircuit clears before this upstream RCCB sees it, keeping the rest of the board live. Voltage-independent tripping means the electromechanical mechanism stores enough energy from the fault current itself to open the contacts — no auxiliary supply needed, so it still protects even if the neutral is lost upstream. The rated conditional short-circuit current of 10 kA tells you the upstream MCB or fuse must be rated to interrupt at least that level; pair this RCCB with a 10 kA breaking-capacity MCB to maintain the full SCCR. Rated impulse withstand voltage of 6 kV and pollution degree 3 suit it for standard industrial panel environments where transient overvoltages and conductive dust are expected.
Neutral on the left. Tightening torque 3.5 N.m. IP20 finger-safe on the front, IP40 inside a modular enclosure. Padlocking provision for lockout/tagout.