The Siemens SENTRON 5SY4401-5 is a 4-pole miniature circuit breaker with a Type A tripping characteristic, designed for AC circuits up to 400 V (440 V multi- or single-phase) and DC circuits up to 60 V (72 V max). Its breaking capacity reaches 10 kA per IEC/EN 60898-1 and 35 kA per IEC 60947-2, with a DC rating of 15 kA per IEC 60947-2 and 5 kA per UL 1077 / CSA C22.2 No.235.
The 5SY4401-5 carries three distinct interrupting ratings: 10 kA under IEC/EN 60898-1 (the standard for household and similar installations), 35 kA under IEC 60947-2 (industrial circuit-breaker standard), and 5 kA under UL 1077 / CSA C22.2 No.235 for North American supplementary protection. The DC rating of 15 kA at 60 V (72 V max) covers DC bus or battery-string protection where the arc is harder to extinguish than on AC.
Environmental and installation constraints
Rated for an ambient range of -40 °C to 75 °C, with derating above 55 °C: max 95 % RH up to 55 °C, then 55 % RH up to 70 °C, then 35 % RH up to 75 °C. Vibration resistance per IEC 60068-2-6: ±1 mm at 5–25 Hz, 50 m/s² at 25–150 Hz — sufficient for mounting on machine frames or near rotating equipment. Halogen-free and silicon-free construction avoids corrosive off-gassing in sealed cabinets.