The Siemens 5SL6125-6CC is a SENTRON miniature circuit breaker (MCB) from the 5SL6CC design family, rated 25 A at 400 V AC with a B tripping characteristic and a 6 kA breaking capacity per EN 60898.
Single-pole (1P) construction, 18 mm wide — one width unit on a standard DIN rail. Wire range accepts 0.75 to 25 mm² solid or stranded; screw terminals torque to 2.5–3 N·m. Mounting position any, IP20 with conductors connected — fine for enclosed panels; not rated for wet environments. Halogen-free and silicon-free construction suits installations where outgassing during a fault must be controlled (hospitals, data centers).