Rated current and breaking capacity
The Schneider Electric A9P54740 Acti9 iC40N is a 40 A miniature circuit breaker in a 3P+N configuration — three protected poles plus a switched neutral on the left. Its C-curve (magnetic trip 5–10 x In) suits general-purpose distribution circuits with moderate inrush, such as lighting banks, small motor groups, or mixed resistive-inductive loads. The breaking capacity is dual-rated: 10 kA Icu at 400 V AC per EN/IEC 60947-2 for industrial panel duty, and 6000 A Icn at 400 V AC per EN/IEC 60898-1 for domestic or commercial final circuits.
This breaker carries dual certification to EN/IEC 60898-1 (the household MCB standard) and EN/IEC 60947-2 (the industrial circuit-breaker standard). That dual rating is the key differentiator from a standard domestic MCB: the 60947-2 rating gives you a higher Icu (10 kA) and a pollution degree 3 classification, meaning it's certified for use in industrial enclosures where conductive dust or humidity is present. Limitation class 3 per 60898-1 means it limits let-through energy effectively, reducing stress on downstream equipment during a fault. Quality marks from OVE, IMQ, and AENOR confirm acceptance in Austrian, Italian, and Spanish markets respectively.
Width is 54 mm (6 x 9 mm pitches), height 85 mm, depth 74 mm — occupies the same footprint as a standard 3P+N MCB in the Acti9 range. Tunnel terminals accept 1–16 mm² rigid or 1–10 mm² flexible cable; tightening torque 2 N.m. Wire strip length 14 mm. Separate earth-leakage block can be added downstream if required.