The Siemens 5SY8650-7 is a SENTRON miniature circuit breaker — 4-pole (3P+N), 50 A rated current, C characteristic. It interrupts faults up to 25 kA at 400 V AC per IEC 60947-2, which means it clears bolted faults on a 400 V distribution bus without upstream devices having to trip. The 15 kA DC rating per IEC 60947-2 covers DC-side protection in rectified supplies. Under UL 1077 and CSA C22.2 No. 235 it holds a 5 kA interrupting rating — that's the number to use for North American supplementary protection listings.
Integration & Mounting
Mounts on DIN rail via the quick assembly system — 4 modular width units wide (72 mm), 70 mm installation depth, 76 mm overall depth. Any mounting position is allowed. The IP20 rating (with connected conductors) is standard for enclosed panelboard use, not for open washdown areas. Combined terminals top and bottom simplify busbar and outgoing wiring. Neutral conductor switching is integrated — no separate neutral link needed.
Environmental & Compliance
Rated for ambient temperatures from -40 °C to +75 °C. Derate the 50 A rating at elevated temperatures: 48.95 A at 50 °C, 47.85 A at 55 °C. Degree of pollution 3, overvoltage category III — suitable for industrial environments with conductive pollution. Halogen-free and silicon-free construction. Vibration resistance per IEC 60068-2-6: ±1 mm at 5–25 Hz, 50 m/s² at 25–150 Hz. Suitability marked for mechanical engineering and industry.
Lockout & Touch Protection
The breaker is sealable — padlockable in the OFF position for positive isolation during maintenance. Touch protection is built in per the product feature. If it's not locked, it's not safe — this one accepts a lock.