What the ratings mean for fit
The A9F04103 is a 1-pole Acti9 iC60N miniature circuit breaker with a C-curve, rated 3 A. Magnetic tripping occurs at 8 x In +/- 20 %. Breaking capacity is the headline here: 50 kA Icu at 240 V AC per EN/IEC 60947-2, and 6 kA Icn at 230 V AC per EN/IEC 60898-1. The Icu figure (ultimate breaking capacity) tells you it can safely interrupt a 50 kA fault once — enough for high-fault industrial panels. The Icn (rated short-circuit capacity) at 6 kA is the domestic/commercial standard. If your panel's prospective short-circuit current exceeds 6 kA at the breaker, you rely on the 60947-2 rating; if it's under 6 kA, either standard applies. For DC circuits, it breaks 15 kA at 12…60 V DC and 10 kA at 60…72 V DC. Rated insulation voltage is 500 V AC, and overvoltage category IV means it's rated for the mains supply point (not just downstream equipment). Pollution degree 3 (conductive pollution or dry non-conductive that becomes conductive) is typical for industrial control panels — no extra derating needed for dusty or humid environments.
Integration and mounting
Mounts on a DIN rail — 2 modules wide (18 mm per pitch). The double terminal accepts up to 25 mm² rigid or 16 mm² flexible wire, top or bottom. IP20 rated — suitable for enclosed distribution boards, not for washdown or outdoor exposure. Tropicalisation class 2 per IEC 60068-1 means it's treated against humidity and fungal growth for warm, damp environments.