Integrator note — 5SL4240-7CC
The Siemens SENTRON 5SL4240-7CC is a 2-pole miniature circuit breaker with a C tripping characteristic, rated 40 A at 400 V AC and 10 kA breaking capacity per EN 60898. The 2-pole design (2 MW units wide, 36 mm) gives you a switched neutral or a 2-phase feed in a single module.
Rated 40 A at 30 °C ambient. At 40 °C it's 36.96 A, at 45 °C it's 35.34 A, at 50 °C it's 33.64 A, and at 55 °C it's 31.85 A. The breaker's thermal-magnetic element is calibrated to these derated values; ignoring them means nuisance tripping on a warm day.
Depth is 76 mm overall, installation depth 70 mm. Mounting position is any, so horizontal DIN-rail layouts in shallow enclosures are fine. Pollution degree 2 (normal industrial environment, no condensation). IP20 with connected conductors — keep it inside a closed cabinet.
The 5SL4 series is Siemens' standard residential and light-commercial MCB line. Halogen-free and silicon-free construction, which matters for clean-room or semiconductor-adjacent installs where outgassing contaminates optics or wafers. Sealable (can be padlocked in OFF position for lockout/tagout). Suitability for residential buildings and infrastructure per the manufacturer's classification.