Siemens 5SL4201-7CC SENTRON MCB – 2-pole, C-curve, 1 A
The Siemens 5SL4201-7CC is a 2-pole miniature circuit breaker from the SENTRON family, rated 1 A with a C tripping characteristic and a 10 kA breaking capacity at 400 V AC per EN 60898. That 10 kA SCCR means it can safely clear a fault up to 10,000 A without welding its contacts or cascading the fault upstream — important for selectivity in a residential or light commercial distribution board where the upstream main breaker is typically rated higher.
This MCB occupies 2 modular width units (36 mm) on a standard DIN rail, with a depth of 76 mm and a 70 mm installation depth — it sits flush with the rail and leaves room for wiring behind the panel door. Vibration resistance to 50 m/s² at 25–150 Hz per IEC 60068-2-6 means it holds up on a machine panel or in a mobile installation.
At 30 °C ambient, the MCB carries its full 1 A rating. At 40 °C it derates to 0.95 A, at 45 °C to 0.92 A, and at 50 °C to 0.89 A. By 55 °C you're down to 0.86 A.