The Schneider Electric A9F43401 is an iC60N miniature circuit breaker from the Acti9 range, rated 1 A with 4 protected poles and a B tripping curve. It carries a 50 kA Icu breaking capacity at 415 V AC per EN/IEC 60947-2, and 6 kA Icn per EN/IEC 60898-1 — dual-rated so it fits both residential distribution boards and industrial panel schedules. The thermal-magnetic trip unit triggers magnetically at 4 x In (±20 %), which for a 1 A breaker means instant trip above roughly 4.8 A; the B curve is standard for resistive or light inductive loads where you want fast short-circuit clearance without nuisance tripping on inrush.
Breaking capacity and dual standard
Rated Icu of 50 kA at 415 V AC under EN/IEC 60947-2 means this breaker can safely interrupt a 50 kA prospective fault current without welding its contacts — that is industrial-grade fault clearance for a 1 A device, usually found in sub-distribution boards fed by a large transformer. The limitation class is 3 per EN/IEC 60898-1, meaning it limits let-through energy well enough to protect downstream equipment in a coordinated system.
Clip-on mounting onto a standard DIN rail, 9 mm pitch occupies 8 modules (72 mm wide). The 4-pole format with a toggle control and a trip indicator gives visual confirmation of the tripped pole.