The Schneider Electric A9V31425 is an Acti9 Vigi iC60 add-on residual current device — a 4-pole block rated 25 A with 30 mA earth-leakage sensitivity, Type A-SI (Super Immunised). It clips onto the DIN rail alongside the matching iC60 MCB and connects via screw terminals. The 30 mA trip threshold covers standard personnel protection in AC networks, while the Type A-SI designation means it handles pulsed DC fault currents and resists nuisance tripping from high-frequency harmonics or transient surges common on modern electronic loads.
The 25 A rated current matches the iC60 MCB it pairs with — sized for a 25 A outgoing circuit. Type A-SI (Super Immunised) is the key differentiator: it is designed to stay latched through 8/20 µs impulse surges up to 3000 A without tripping, which matters on circuits with switching power supplies, VFDs, or LED drivers that generate high-frequency leakage. The voltage-independent tripping technology means the RCD operates without needing a separate power supply — it uses the fault energy itself to trip, so it works even if the neutral is lost upstream.
Mounts via clip-on to standard DIN rail, occupying 6 modules of 9 mm pitch (54 mm total width). The trip indicator gives a local visual signal after a fault event, which speeds troubleshooting on a live panel.