The Siemens 5SL4101-7 is a SENTRON miniature circuit breaker, 1-pole, C-curve, rated 1 A at 230/400 V AC with a 10 kA breaking capacity per EN 60898 and IEC 60947-2. That 10 kA rating means it safely interrupts a fault current up to that level without welding the contacts or cascading upstream — sized for residential and light commercial distribution boards where the prospective short-circuit current stays under that threshold.
DIN-rail fit and panel integration
Width is 18 mm — one modular unit (1 MW) — so it snaps onto standard DIN rail and occupies a single slot in a distribution board. Depth of 76 mm (70 mm installation depth) means it clears most enclosure gland plates without a spacer. Mounting position is any, which simplifies layout in tight enclosures.
Thermal derating and real-world current
Rated 1 A at 30 °C ambient, but the continuous current drops to 0.95 A at 40 °C, 0.92 A at 45 °C, and 0.86 A at 55 °C. If the panel runs warm — say 45 °C inside a sealed enclosure — that 1 A breaker is good for about 0.92 A continuous. The power loss per pole is 1.2 W at rated current in hot operating state, which matters for thermal budgeting in a multi-pole assembly.
Rated supply voltage frequency is 50/60 Hz. Single-phase operation at 250 V AC; multi-phase at 440 V AC maximum. Energy limitation class 3. The C-curve characteristic (tripping between 5× and 10× In) suits moderate inrush loads — lighting banks, small transformers, control circuits — where a B-curve would nuisance-trip and a D-curve would be too slow for cable protection.