The A9F05225 is a 2-pole miniature circuit breaker from the Acti9 iC60N family, rated 25 A with a D tripping curve. The D curve means magnetic trip occurs at 12× In (±20%) — that's 300 A instantaneous, give or take 60 A — sized for motor and transformer inrush where standard B or C curves would nuisance-trip on start-up. The 36 kA Icu at 12–133 V AC and 20 kA at 220–240 V AC tells you it safely interrupts fault currents up to those levels without welding or cascading upstream. That's IEC 60947-2 industrial breaking capacity, not just the 6 kA Icn under IEC 60898-1 for residential service. If your panel feeds a motor branch or a mixed inductive load, this is the curve you want.
Deployment context
The IP20 finger-safe terminals accept up to 25 mm² rigid or 16 mm² flexible, with a 14 mm strip length and 2 N·m torque. The thermal-magnetic trip unit handles both overload and short-circuit; the separate earth-leakage block (not included) can be added downstream if you need residual-current protection.