The Siemens 5SL4225-8CC is a SENTRON 5SL miniature circuit breaker (MCB) with a D tripping characteristic, rated 25 A at 400 V AC, and a 10 kA breaking capacity per EN 60898. The 2-pole construction (2P) switches both phase conductors in a single-width envelope of 2 modular units (36 mm), so it fits a standard DIN-rail panel position without crowding adjacent breakers.
What the D-curve and 10 kA mean for your panel
At 25 A, the D-curve holds through the magnetizing inrush of a small motor or the charging current of a capacitor bank, then clears a hard fault at the 10 kA SCCR level. That 10 kA rating at 400 V AC (per EN 60898) means this breaker can safely interrupt a prospective short-circuit current up to 10,000 A without welding contacts or cascading failure upstream — a key coordination point for the panel designer sizing the main breaker or fuse.
Rated IP20 with connected conductors, so it is intended for enclosed distribution boards or control cabinets, not washdown or outdoor exposure.