The Schneider Electric A9N16251 is a 4-pole residual current circuit breaker (RCCB) from the Acti9 xID range, rated 25 A with 30 mA earth-leakage sensitivity — the standard threshold for personal protection against direct contact in residential and light commercial final circuits. Breaking and making capacity is 500 A per EN/IEC 61008-1 — adequate for the fault-current levels typical of a sub-distribution board, not a main incomer. The instantaneous trip time means no intentional delay; nuisance tripping on motor-start inrush or capacitive loads is a risk to plan for. Neutral on the left, which is the standard for Schneider distribution boards.
Compliance documentation covers EN/IEC 61008-1 and IEC 61008-2-1, plus tropicalisation class 2 per IEC 60068-1 (handles 95 % RH at 55 °C). Pollution degree 2 — suitable for normal industrial and commercial environments where only non-conductive pollution occurs, with occasional condensation. IP20 finger-safe terminals; no washdown rating, so mount inside a panel or enclosure.
Integration Notes
DIN-rail clip-on, 4-pole wide (72 mm), 81 mm tall, 75 mm deep. The 18 mm phase-to-phase pitch matches standard Acti9 busbar systems. Torque terminals to 3.5 N·m top or bottom; strip 14 mm of insulation. Padlocking provision for lockout/tagout on the toggle. Local signalling shows ON, OFF, and fault trip — no auxiliary contact built in, so remote status requires an external add-on. Mechanical and electrical durability are both rated at 4000 cycles — fine for a distribution RCCB switched infrequently. For frequent switching duty (e.g. as a manual disconnect on a machine), consider a contactor or switch-disconnector instead; the RCCB is a protection device first.