The Siemens 5SY4204-6CC is a SENTRON miniature circuit breaker (MCB) with a B tripping characteristic, rated at 4 A at 40 °C and 10 kA breaking capacity per EN 60898.
Two modular width units (MW) wide at 36 mm, depth 76 mm, height 90 mm. Installation depth 70 mm. IP20 with connected conductors, so it lives inside a closed enclosure.
Thermal environment and derating
Rated 4 A at 35 °C, but derates to 3.76 A at 40 °C, 3.64 A at 45 °C, 3.5 A at 50 °C, and 3.37 A at 55 °C.
