The Schneider Electric A9R11440 is a 4-pole residual current circuit breaker (RCCB) from the Acti9 iID family, rated 40 A with 30 mA earth-leakage sensitivity. The 40 A thermal rating matches the upstream MCB or the load's full-load current; it is not a motor-protection device, so size it for the circuit's continuous current, not the starting inrush. If the downstream load includes VFDs, UPS systems, or LED drivers that can generate smooth DC leakage, a Type A or Type B RCCB would be needed instead. Voltage-independent tripping means the RCCB does not need a separate power supply or the line voltage to operate — the fault energy itself drives the trip mechanism. This makes it fail-safe against a lost neutral or a supply dropout, which is critical for continuity of protection in older TN-C-S systems or where the neutral conductor is unreliable.
The 72 mm width occupies 8 modular pitches of 9 mm, so it fills four standard 18 mm MCB ways — plan the enclosure fill factor accordingly. Neutral is on the left, which dictates busbar orientation in a split-bus or dual-row panel. The IP20 finger-safe terminals are fine for enclosed panels; the IP40 modular enclosure rating means it is protected against tools and small wires entering the device body when mounted in a distribution board.
Designed and certified to EN/IEC 61008-1, the harmonized standard for RCCBs in household and similar installations.