The A9Q44340 is a voltage-independent add-on residual current device (RCD) from the Acti9 Vigi iC60 family — clips onto the outgoing side of a compatible iC60 MCB to add earth-leakage protection without extra wiring. The 40 A rated current and 300 mA sensitivity mean it's sized for sub-distribution or feeder circuits where the load draws up to 40 A and you need a higher trip threshold to avoid nuisance tripping from leakage in long cable runs or industrial loads. Type AC detection handles sinusoidal AC residual currents only — fine for general lighting, socket outlets, and resistive loads, but not for pulsed or DC-ripple waveforms from VFDs, UPS, or EV chargers. The 230...415 V AC operational voltage covers single-phase and three-phase networks within that range. Voltage-independent tripping means the RCD disconnects even if the phase voltage collapses — a safety advantage for circuits where loss of neutral could otherwise mask a fault.
Clip-on mounting on standard DIN rail — snaps directly onto the rail beside or downstream of the iC60 MCB. The plug-in electrical connection to the MCB means no additional phase wiring; the RCD draws its supply through the MCB's outgoing terminals. Occupies 7 modules of 9 mm pitch, so 63 mm total width. Depth of 73.5 mm fits standard distribution boards and enclosures; verify gland-plate clearance if the board is shallow. IP20 finger-safe for enclosed panels; IP40 when installed in a modular enclosure. Tightening torque 3.5 N.m.