Siemens 5SY5140-6CC — SENTRON 1P DC MCB, B-Char 40A
It carries a B tripping characteristic and is rated 40 A at 35 °C, with a 220 V DC operating voltage and a 10 kA DC breaking capacity per IEC 60947-2. Rated current derates with ambient temperature: 38 A at 40 °C, 36.96 A at 45 °C, 35.92 A at 50 °C, and 34.8 A at 55 °C. This is a single-pole unit with no neutral switching. Polarity must be observed on the DC supply. IP20 with connected conductors means the terminals are finger-safe once wired, but the breaker itself isn't sealed against washdown — it's a panel-mount part, not a field device.
Environmental & Compliance
Sealable design allows the panel builder to lock the toggle position after commissioning. Vibration resistance per IEC 60068-2-6: ±1 mm at 5 to 25 Hz, 50 m/s² at 25 to 150 Hz. That covers most rotating machinery and conveyor applications without nuisance tripping from vibration. Operating temperature range -40 to 75 °C. Humidity derating applies: max 95% RH up to 55 °C, tapering to 35% RH at 75 °C.