The A9N18500 is a 2-pole miniature circuit breaker from the Acti9 C120H range, rated 63 A at 30 °C with a D tripping curve (magnetic trip 10–14 × In). The D curve means it tolerates the high inrush of motor and transformer loads without nuisance tripping — the magnetic trip won't fire until the fault hits 10 to 14 times the 63 A rating, so a 3-phase motor starting at 6× FLC coasts right through. Breaking capacity is 15 kA Icn at 400 V AC per EN/IEC 60898-1, and 10 kA Icu at 440 V AC per EN/IEC 60947-2 — that's enough for most industrial distribution panels downstream of a 200 kVA transformer.
Dual-standard compliance and isolation
This breaker carries both EN/IEC 60898-1 (MCB standard) and EN/IEC 60947-2 (industrial circuit-breaker standard) approvals. That dual rating means it's accepted for residential and commercial boards (60898-1) and for industrial panels where the higher Icu and isolation requirements of 60947-2 apply.