The Schneider Electric A9R82440 is a 4-pole residual current circuit breaker (RCCB) from the Acti9 iID family, rated at 40 A with 300 mA earth-leakage sensitivity. The breaking and making capacity is rated at 1500 A (Idm and Im), which covers the fault-clearing requirement for most sub-distribution outgoers in a commercial or light-industrial panel.
The 4-pole body takes 8 x 9 mm pitches — that's 72 mm of rail width — so plan your enclosure fill accordingly. Neutral is on the left, which matters for busbar alignment in a pre-wired distribution board. Strip length is 14 mm.
