The A9P52740 is a 40 A, 3P+N miniature circuit breaker from the Schneider Electric Acti9 iC40 series, rated for distribution applications on AC networks at 50/60 Hz. The C curve (magnetic trip at 5 to 10 x In per EN/IEC 60898-1, or 8 x In ±20 % per EN/IEC 60947-2) means it tolerates moderate inrush, typical for motor starters, small transformers, or lighting banks, without nuisance trips on startup. Breaking capacity is the real fit gate: 4500 A Icn under EN/IEC 60898-1 at 400 V AC, and 6 kA Icu under EN/IEC 60947-2 at the same voltage. The dual-standard rating also means it qualifies for both residential/commercial (60898-1) and industrial (60947-2) applications, which simplifies spec for mixed-use panels.
Construction and mounting
Clip-on mounting to DIN rail, 6 modules wide at 9 mm pitch (54 mm total). Neutral is on the left, poles are 3P+N with three protected poles. Tunnel terminals accept 1 to 16 mm² rigid or 1 to 10 mm² flexible, with a tightening torque of 2 N.m. Trip technology is thermal-magnetic — the thermal bimetal handles overload protection, the solenoid handles short-circuit. The magnetic tripping limit of 5 to 10 x In (60898-1) or 8 x In ±20 % (60947-2) is the band within which instantaneous trip occurs; below that, the thermal element takes over with an inverse-time characteristic. Local signalling includes ON/OFF indication and a separate trip indicator, plus a contact position indicator for isolation verification — the breaker is certified for isolation per EN/IEC 60947-2.