The Schneider Electric A9V01240 is an add-on residual current device (RCD) from the Acti9 Vigi iC60 range, designed to clip onto the outgoing side of an iC60 MCB. It provides earth-leakage protection for a 2-pole circuit, rated at 40 A with a 30 mA sensitivity, Type AC (sinusoidal AC residual currents only). The unit is voltage-independent — the tripping mechanism does not rely on the line voltage to detect a fault, which means it remains functional even if the neutral is lost upstream.
The 40 A rated current (In) sets the continuous load this RCD can carry — sized for a 40 A feeder or submain, not for a final subcircuit below that rating. The 30 mA sensitivity is the standard for personal protection against indirect contact in most residential and commercial installations per IEC 60364. The voltage-independent tripping technology is a differentiator: the RCD stores enough energy from the fault current itself to trip the mechanism, so a lost neutral or a voltage sag on the supply side does not disable protection. This is standard for most electromechanical RCDs but worth confirming if the specification calls for it explicitly.
Clip-on mounting to DIN rail (EN/IEC 60715). The unit occupies 4 modules of 9 mm pitch (72 mm total width). It is an add-on block that screws directly to the outgoing side of an iC60 MCB — the electrical connection is made via screws, not busbars, so the assembly forms a single combined RCBO-like unit. IP20 on the device body, IP40 when enclosed in a modular enclosure per IEC 60529.
The 8/20 µs impulse withstand rating of 250 A per IEC 61009-1 confirms the device can survive common surge currents without nuisance tripping.