The Schneider Electric A9F03740 is an Acti9 iC60N miniature circuit breaker rated 40 A with a B-curve trip characteristic, 3 protected poles plus neutral (3P+N). It carries dual certification to EN/IEC 60898-1 and EN/IEC 60947-2, meaning it qualifies for both residential and industrial distribution panel duty. Breaking capacity is the headline spec here: 36 kA Icu at 12…133 V AC, 20 kA at 220…240 V, 10 kA at 380…415 V, and 6 kA at 440 V under IEC 60947-2. For the 60898-1 rating it delivers 6000 A Icn at 400 V.
The B-curve trips magnetically at 4 x In ±20 %. It suits resistive and general-purpose loads with low inrush. Thermal-magnetic trip technology means the bimetal element handles overload protection (time-delayed, inversely proportional to current) while the solenoid handles short-circuit interruption. The 3P+N configuration switches all three phases and breaks the neutral pole, though the neutral is not protected — it is a switched neutral, not a monitored pole.
DIN-rail panel integration
The 72 mm width (8 x 9 mm pitches) occupies three modular spaces plus one for the switched neutral. Double terminals top and bottom accept 1…35 mm² rigid or 1…25 mm² flexible cable; tightening torque 3.5 N.m. Strip length 14 mm. The IP20 finger-safe terminals suit enclosed panel use — not for exposed outdoor installation without an enclosure.
Dual-certified to EN/IEC 60898-1 (the household-standard for MCBs) and EN/IEC 60947-2 (the industrial-standard for low-voltage switchgear). Suitability for isolation is affirmed under both standards, meaning the breaker can serve as a visible-break disconnect when locked off. The contact position indicator (red/green flag on the toggle) gives visual confirmation of the contact state. Rated for AC and DC networks at 50/60 Hz. Earth-leakage protection requires a separate Vigi iC60 block — it is not integral. The limitation class 3 rating under 60898-1 means it limits let-through energy well, reducing stress on downstream equipment during a fault.