What this 10 A C-curve MCB covers
The Siemens 5SL4210-7CC is a 2-pole miniature circuit breaker from the SENTRON family, rated 10 A at 30 °C with a C tripping characteristic — the standard choice for protecting general-purpose circuits feeding motor starters, contactor coils, and small power supplies in residential and light-industrial distribution boards. At 400 V AC it interrupts fault currents up to 10 kA per EN 60898, which is the typical SCCR requirement for most commercial panelboards.
At 40 °C ambient the breaker derates to 9.24 A; at 45 °C to 8.83 A; at 50 °C to 8.41 A; at 55 °C to 7.96 A. The 2-pole body occupies 2 modular width units (36 mm wide) and mounts in any position. IP20 with connected conductors is fine for dry indoor panels; not rated for washdown.