What it is and what it does
The Siemens 5SL4102-7RC is a 1-pole SENTRON miniature circuit breaker with a C tripping characteristic, rated 2 A at 240/415 V AC and a 10 kA breaking capacity per EN 60898. That 10 kA rating means it can safely interrupt fault currents up to 10,000 A on a 415 V three-phase network without welding its contacts or rupturing the case — critical for coordination with downstream loads in a residential or light-commercial distribution board. The C-curve (tripping between 5× and 10× In) makes it a fit for circuits with moderate inrush — think lighting banks, small motor starters, or general socket outlets — where the magnetic trip needs to ride out a brief start-up surge without nuisance tripping.
Panel fit and handling
At 18 mm wide (1 modular width unit), it snaps onto a standard DIN rail and occupies one slot in a consumer unit or sub-distribution board. Installation depth is 70 mm, overall depth 76 mm — enough clearance for most enclosure backplates without bottoming out against the rear gland plate. Rated IP20 with connected conductors, so it's protected against finger contact but not washdown — keep it inside a dry enclosure. The breaker is sealable (provision for a lockout tagout hasp) and accepts auxiliary switches, shunt trips, or alarm contacts via the accessory slot on the left side.