The Schneider Electric A9W22425 is an add-on residual current device (RCD) from the Acti9 Vigi iC60 range, designed to clip onto the side of an iC60 MCB (with double terminal) to add earth-leakage protection to the outgoing circuit. It is a 4-pole unit rated at 25 A, with a 100 mA sensitivity, Type A (pulsating DC and sinusoidal AC fault detection), instantaneous trip, for 230/415 V AC networks at 50/60 Hz. Mounting is clip-on to DIN rail, and the device occupies 6 modules of 9 mm pitch — 126 mm width. The 74 mm depth and 91 mm height fit standard modular enclosures.
The 25 A rated current matches the iC60 MCB it attaches to — you pair this RCD with a 25 A breaker on the same outgoing circuit. The 100 mA sensitivity is a deliberate choice: higher than the 30 mA used for personal shock protection, so it's intended for equipment protection or circuits where nuisance tripping from normal leakage (long cable runs, filtered loads) would be a problem. Type A means it detects sinusoidal AC faults plus pulsating DC faults up to 6× the rated sensitivity — covers most modern electronics and VFD-fed loads. Rated operational voltage is 230/415 V AC — single-phase line-to-neutral or three-phase line-to-line. The insulation voltage is 500 V AC, and impulse withstand is 6 kV, which is standard for distribution boards in industrial and commercial installations. The residual current tripping technology is voltage independent — no auxiliary supply needed to detect a fault. That's a reliability advantage: the RCD trips even if the neutral is lost upstream.
Installation and wiring notes
Electrical connection to the MCB is by screws — the RCD bolts directly to the iC60's double terminal, so the busbar passes through both devices. IP20 on the device body, IP40 on the modular enclosure — fine for a distribution board; not rated for washdown. Ambient operating range -25…60 °C, storage -40…85 °C.