What this RCCB is and what it guards
The Schneider Electric A9R11292 is a 2-pole residual current circuit breaker (RCCB) from the Acti9 range, rated 125 A at 230 V AC, 50 Hz, with 30 mA earth-leakage sensitivity and Type AC protection.
125 A rated current (In) and 230 V operational voltage (Ue) set the load envelope: this RCCB handles the full incoming feed for a sub-distribution board or a high-load outgoer, not just a final subcircuit. The 30 mA sensitivity (IΔn) is the standard for personal protection against indirect contact — it's fast enough to clear before heart fibrillation sets in. The breaking capacity Im is 1250 A at 230 V — that's the maximum prospective fault current the RCCB can interrupt without welding contacts, and it's well above typical domestic fault levels but below what you'd see on a heavy industrial bus.
Tunnel-type terminals accept 1.5–50 mm² rigid or 1.5–35 mm² flexible (single cable), or 1.5–16 mm² with two cables per pole. Tightening torque is 3 N·m; strip length 11 mm. IP20 on the body, IP40 inside a modular enclosure — fine for dry indoor distribution boards, not for washdown areas.
Certified to IEC/EN 61008-1 and IEC/EN 61008-2-1 (the RCCB product standards). Carries VDE quality label. Ambient storage range -40 to 85 °C.