The Siemens 5SL6316-7YA is a SENTRON miniature circuit breaker (MCB) — a 3-pole unit rated 16 A with a C tripping characteristic and a 6 kA breaking capacity at 400 V AC per EN 60898. This is the standard residential and light-commercial MCB for branch-circuit overcurrent and short-circuit protection on 400 V three-phase systems.
Rated 400 V AC for multi-phase operation, 50/60 Hz — drop it into a standard 3-phase panelboard on a 400/230 V distribution system. The IP20 rating applies only with the distribution board cover fitted — the breaker itself is not touch-safe without the enclosure. The 3-pole design switches all three phases simultaneously, so it suits a three-phase load or a three-phase supply feeding single-phase sub-circuits. DC rated to 72 V maximum — usable on DC control circuits at that voltage, but the AC rating is the primary spec. Dimensions are 54 mm wide (3 modular width units), 90 mm tall, 76 mm deep with a 70 mm installation depth.
If you need add-on accessories, the 5SL4363-7 sibling supports them and shares the same footprint and 3-pole C-curve format, though with a higher 10 kA breaking capacity. That is a genuine cross-reference for panels that require accessory slots or higher SCCR.