1-pole D-curve MCB for high-inrush loads
The Siemens 5SL4104-8CC is a SENTRON miniature circuit breaker with a D tripping characteristic, rated 4 A at 400 V AC across a single pole. The D-curve means the magnetic trip fires at 10–20× In, so it holds through the inrush of motor starters, solenoid valves, and small transformers without nuisance tripping — the standard choice for inductive and high-starting-current branch circuits in residential and light-infrastructure panels.
Breaking capacity and selectivity
Rated short-circuit breaking capacity is 10 kA per EN 60898 at 230/400 V AC. That's the standard domestic and commercial distribution board rating; it interrupts fault currents up to 10 kA without welding the contacts. Overvoltage category III and pollution degree 2 confirm it's rated for fixed-installation downstream of a service entrance — not for primary distribution, but fine for sub-distribution where the upstream device limits prospective fault current to 10 kA or less.
Physical fit and panel integration
Single modular width unit (18 mm) on DIN rail, depth 76 mm, installation depth 70 mm. Occupies one 18 mm slot — same footprint as any 1-pole SENTRON 5SL4. Mounting position any; no derating for horizontal or inverted rail orientation. IP20 with connected conductors, so it's enclosed inside the distribution board cover. Sealable design allows the installer to lock the toggle position after commissioning.