The Siemens SENTRON 5SL4240-8CC is a 2-pole miniature circuit breaker rated 40 A at 400 V AC, with a D tripping characteristic and a 10 kA breaking capacity per EN 60898. The D-curve means it tolerates high inrush currents — typical for motor, transformer, or lighting ballast loads — without nuisance tripping, while still clearing a hard fault within the 10 kA rating. Mounts on a standard DIN rail, occupies 2 modular width units (36 mm wide), and is rated for any mounting position.
Thermal derating and ambient range
Rated 40 A at 30 °C ambient, the breaker derates to 37.89 A at 40 °C, 36.78 A at 45 °C, 35.65 A at 50 °C, and 34.47 A at 55 °C. If your panel ambient runs above 30 °C, size the load to the derated value at that temperature. The operating range spans -40 °C to 75 °C, so it handles cold storage or rooftop enclosures without issue.
Material and environmental specs
Halogen-free and silicon-free construction — relevant for cleanroom or semiconductor-fab environments where outgassing or particle contamination from standard plastics could affect yield. Pollution degree 2, overvoltage category III, and IP20 with connected conductors. Vibration resistance tested to 50 m/s² at 25 to 150 Hz per IEC 60068-2-6, so it holds up on machinery or near rotating equipment.
Lifecycle and compliance
Listed as current production — no end-of-life notice on record. The 5SL4240-8CC carries a 10 kA breaking capacity at 400 V AC per EN 60898, and a maximum 440 V AC for multi-phase operation. The product designation is miniature circuit breaker; the brand is SENTRON. Compliance documentation (RoHS, REACH, UL, IEC) is typically provided with the unit or available on request — confirm at quote time.