What it is and what it does
The Siemens SENTRON 5SN4110-7CN is a 1-pole miniature circuit breaker with a C-curve trip characteristic, rated 10 A and 10 kA breaking capacity per EN 60898 at 400 V AC. That 10 kA interrupting rating means it can safely clear a fault current up to 10,000 amps without welding its contacts or venting arc gas into the panel — essential for downstream coordination in a distribution board where the upstream device may be a 25 kA or 36 kA main breaker. The C-curve (5 to 10 times In magnetic trip) suits it for mixed resistive and moderate inductive loads like small motor circuits, lighting banks, and control transformers where you need a bit of inrush headroom without moving to a D-curve. It occupies a single modular width (18 mm) on a DIN rail, with a 70 mm installation depth and 76 mm total depth including the toggle. The IP20 rating with connected conductors means it's protected against finger contact once wired, but not against water ingress — standard for indoor panel use. Rated for any mounting position, so you're not stuck with a specific orientation on a crowded rail.
Panel integration notes
Snaps onto a standard 35 mm DIN rail, one module wide. The sealable feature means you can lock the toggle position with a lead seal or a padlock hasp accessory — useful for utility-metering applications or where you need to prevent unauthorized reset. Accepts solid conductors up to 25 mm², which is generous for a 10 A breaker; you can land a 4 mm² or 6 mm² feeder without needing a ferrule. Supplementary devices like shunt trips or auxiliary contacts can clip onto the left side without losing the next module position.
Environmental and compliance
Halogen-free and silicon-free construction matters in railway, aerospace, or clean-room panels where outgassing from a fault arc can't contaminate sensitive electronics. Rated for ambient temperatures from -40 °C to +75 °C with 95% humidity at 55 °C — that covers unheated enclosures in cold climates and hot electrical rooms. Overvoltage category III and pollution degree 2 confirm it's designed for fixed-installation distribution boards, not plug-in portable use.