The Schneider Electric A9W31263 is an Acti9 Vigi iC60 add-on residual current device (RCD) that clips onto the side of an iC60 MCB — two-pole, rated 63 A, with a 30 mA earth-leakage sensitivity. It's a Type A-SI (Super Immunised) instantaneous trip, meaning it handles pulsed DC fault currents and high-frequency leakage from electronics without nuisance tripping. That SI suffix matters in environments with variable-speed drives or switching power supplies where standard Type A might false-trip.
The 63 A rating matches the upstream MCB's frame — you pair this RCD with a 63 A iC60 breaker, not a smaller one. The 30 mA sensitivity is the standard for personnel protection (shock) per IEC 61009-1. Type A-SI adds immunity to 8/20 µs surge currents up to 3000 A, so it won't trip on lightning or switching transients on the line. Voltage-independent tripping means it clears a ground fault even if the phase voltage collapses — no power supply needed for the trip coil.
It's an outgoer device, meaning it sits downstream of the main breaker, protecting a branch circuit.
Designed to IEC 61009-1 and EN 61009-1 — the IEC standard for RCDs with integral overcurrent protection (though this is an add-on, not a combined device). Rated insulation voltage (Ui) is 500 V AC, and impulse withstand (Uimp) is 6 kV.