Panel fit and ratings
The Siemens 5SL4263-6 is a SENTRON miniature circuit breaker (MCB) in a 2-pole, B-curve configuration rated at 63 A continuous at 30 °C, with a 10 kA breaking capacity per EN 60898 and IEC 60947-2. That 10 kA SCCR at 400 V AC means it can safely interrupt a fault current up to 10,000 A without welding the contacts or cascading upstream — adequate for most residential and light commercial distribution boards where the prospective short-circuit current stays under that threshold. B-curve trips between 3 and 5 times rated current, so it holds through inrush from resistive loads and short lighting circuits but clears fast on a hard fault. At 40 °C ambient the continuous rating derates to 59.67 A; at 55 °C it drops to 54.29 A — factor that into the load schedule if the panel runs hot. The 2-module-wide (36 mm) body snaps onto standard DIN rail in any mounting position, with a 70 mm installation depth behind the panel face. IP20 with conductors connected — fine for enclosed distribution boards; not for wet environments.
Lifecycle and sourcing
Same part, different passport — if you are sourcing cross-border, the 5SL4263-6 carries the same genuine Siemens build regardless of which authorized region it ships from. The manufacturer warranty geofencing is real; let me be transparent — if warranty territory matters to your compliance team, flag it on the RFQ and we will route from the matching region.
Compliance and documentation
Rated for overvoltage category III, pollution degree 2, and energy limitation class 3. The housing is halogen-free and silicon-free, with touch protection on the terminals.