The Siemens 5SJ6110-7KS is a 1-pole SENTRON miniature circuit breaker with a C-curve trip characteristic, rated 10 A at 400 V AC and 6 kA breaking capacity per EN 60898.
For a 10 A C-curve MCB on a 400 V supply, 6 kA is the standard domestic and light-commercial rating — it covers most distribution boards fed by a transformer of up to about 630 kVA. If your fault level at the panel exceeds 6 kA, step up to a 10 kA or 15 kA rated MCB in the same SENTRON family. The C-curve (5–10× In) is the default for general-purpose circuits: lighting, socket outlets, small appliances, and control transformers. It avoids nuisance tripping from inrush that a B-curve would catch, while still clearing fast enough for most branch-circuit faults. For motor-starting or high-inrush loads, a D-curve (10–20× In) would be the better fit. Depth of 76 mm (70 mm installation depth) and 18 mm width per pole let it drop into any standard distribution board or sub-panel without clearance issues.
Halogen-free and silicon-free construction. Sealable to prevent tamper.