What the ratings mean for fit
The Siemens 5SY7350-8 is a 3-pole SENTRON miniature circuit breaker with a D tripping characteristic, rated 15 kA breaking capacity per IEC/EN 60898-1 and IEC/EN 60947-2. That 15 kA holds at 400 V AC and also at 60 V DC — the same fault-interrupt capability on both sides, which simplifies panel design for mixed AC/DC loads. The D curve means it tolerates high inrush currents (motor starts, transformer energization) without nuisance tripping; it's the right choice for motor and industrial loads, not for general lighting or resistive circuits where a B or C curve would be a better fit. Under UL 1077 and CSA C22.2 No. 235 the breaking capacity is 5 kA — that's the supplementary-protector rating for North American panels, not the branch-circuit rating. If your BOM calls for UL 489 branch-circuit listing, this part won't satisfy it; but for supplementary protection inside a listed industrial control panel, the 5 kA SCCR at 440 V AC is adequate for most secondary circuits. The 5SY7350-8 mounts on a DIN rail (quick assembly system), occupies 3 modular width units (54 mm), and can be installed in any position. Depth is 76 mm, installation depth 70 mm. IP20 with connected conductors — standard for enclosed panel use, not for wet or washdown environments. Rated for pollution degree 3 and overvoltage category III, so it's suited for industrial environments where conductive dust or condensation is present. Temperature range is -40 to 75 °C, with humidity derating above 55 °C (95% RH at 55 °C, 55% at 70 °C, 35% at 75 °C). Vibration resistance per IEC 60068-2-6: ±1 mm at 5–25 Hz, 50 m/s² at 25–150 Hz. Halogen-free and silicon-free construction — relevant for sensitive environments like semiconductor fabs or clean rooms where outgassing is a concern.
Compliance documentation
The 5SY7350-8 carries approvals per IEC/EN 60898-1, IEC/EN 60947-2, and UL 1077 / CSA C22.2 No. 235. The manufacturer provides RoHS and REACH declarations as standard for the SENTRON family. No separate documentation request needed — these are included with the product or available on the Siemens support portal.