The Schneider Electric A9R05291 is a 2-pole residual current circuit breaker (RCCB) from the Acti9 iID series, rated 100 A at 220-240 V AC 50/60 Hz with a 300 mA Type A earth-leakage sensitivity and a selective time delay. The 300 mA sensitivity means it is sized for whole-circuit protection rather than individual socket-outlet protection — it trips on higher-magnitude leakage currents typical of distribution feeders or sub-mains, not on the small leakage a person might draw through a hand-held tool. The selective delay (marked S) coordinates with downstream RCCBs so that a fault on a branch trips the closest device first, leaving this main switch still closed — no blackout for the whole panel.
Neutral on the left. Terminals accept 1-35 mm² rigid or 1-25 mm² flexible, with a stripping length of 14 mm and a tightening torque of 3.5 N·m. IP20 on the body, IP40 inside the modular enclosure — protected against solid objects over 1 mm, but not washdown-rated; mount inside a panel for outdoor use. The 73.5 mm depth leaves clearance for standard gland plates and busbar connections.