DC-rated miniature circuit-breaker for 250 V DC bus protection
The Siemens 5SL5250-6CC is a 2-pole miniature circuit-breaker rated for 250 V DC with a 10 kA breaking capacity and a B50 tripping characteristic. The B50 curve means it trips magnetically between 3 and 5 times rated current — fast enough to clear a hard short on a DC bus without nuisance tripping from capacitive inrush on downstream DC-DC converters or filter banks. The 10 kA SCCR at 250 V DC is the key number for panel builders: it tells you this breaker can interrupt a fault up to that level without welding contacts or cascading upstream, so it's sized for sub-distribution in 250 V DC control power systems, UPS output panels, or solar combiner boxes where the prospective fault current stays under that threshold.