The Siemens 5SY4550-8CC11 is a miniature circuit breaker (MCB) rated 230 V with a 10 kA breaking capacity, configured as 1+N-pole, D-curve, 50 A, and specified for railway applications.
Deployment context
This MCB mounts on a standard DIN rail (EN 60715) inside a railway control cabinet or junction box. The D-curve and 10 kA SCCR suit it for branch-circuit protection in 230 V single-phase auxiliary supplies — HVAC, lighting, battery chargers, or door controls — where the prospective fault current at the panel is known to stay under 10 kA.