Siemens SENTRON 5SY4503-7CC — 3 A C-Curve MCB, 2-Pole, 10 kA
Its 10 kA breaking capacity per EN 60898 means it can safely interrupt fault currents up to that level at 230/400 V AC, 50/60 Hz — sufficient for most sub-distribution boards and machine supply circuits where the prospective short-circuit current stays under that threshold.
Panel fit and modular integration
At 36 mm wide (2 modular width units), this breaker occupies two standard 18 mm DIN-rail slots. Rated IP20 with connected conductors — suitable for enclosed panel use.
Thermal derating and ambient conditions
The 3 A rating holds at 35 °C ambient. At 40 °C it derates to 2.82 A, at 45 °C to 2.73 A, at 50 °C to 2.63 A, and at 55 °C to 2.53 A. The breaker operates across -40 °C to 75 °C ambient, with humidity limits of 95% up to 55 °C, 55% up to 70 °C, and 35% at 75 °C. That covers cold storage areas and warm machine cabinets alike.