The Siemens 5SY4350-6CC11 is a 3-pole SENTRON miniature circuit breaker rated 50 A with a B tripping characteristic and 10 kA breaking capacity at 400 V AC per EN 60898. This is the part you grab when the line-down call is a 50 A three-phase lighting or resistive load panel that needs fast overcurrent protection — the B curve trips at 3-5× rated current, so it clears short circuits fast enough to protect sensitive loads without nuisance tripping on mild inrush.
Mounts on a standard DIN rail via the quick-assembly system — snaps on without tools, any position, and the IP20 rating (with connected conductors) means it's fine inside a ventilated enclosure but not for wet panel faces. The 54 mm width (3 width units) and 70 mm installation depth leave room alongside other SENTRON modules on the same rail; the 76 mm overall depth fits standard 80 mm deep enclosures.