What the ratings mean for your panel
The Siemens 5SY6208-8 is a 2-pole miniature circuit breaker from the SENTRON 5SY6 family, rated 8 A at 400 V AC. The D tripping characteristic means it tolerates high inrush currents — typically 10–20× rated current — making it the right choice for motor, transformer, or welding-equipment branch circuits where a B- or C-curve would nuisance-trip on startup. Breaking capacity is 6 kA per EN 60898 for general distribution and 15 kA per IEC 60947-2 for industrial panel applications, so it handles fault currents up to that level without upstream coordination issues in most standard MCCs. At 2 modules wide (36 mm), it snaps onto DIN rail via the quick-assembly system and accepts top/bottom comb busbars — the combined terminal feature means you can feed a busbar through either end without extra adapters. Mounting position is any, and the IP20 rating (with conductors connected) is standard for enclosed panel gear.
Lifecycle and sourcing reality
Approvals include EN 60898, IEC 60947-2, UL 1077 and CSA C22.2 No. 235 — the UL/CSA supplementary-protector rating at 5 kA (480Y/277 V) covers North American panel builds. Halogen-free and silicon-free construction matters for high-reliability or clean-room environments where outgassing can contaminate contacts or optics.
Integration notes
Depth is 76 mm, installation depth 70 mm — check gland-plate clearance if back-panel wiring is tight. The 90 mm height and 36 mm width (2 width units) fit standard Siemens distribution boards and most third-party enclosures. Sealable cover option (yes) allows lockout/tagout compliance without an external hasp. Rated for ambient temperature from -40 °C to 75 °C, with humidity derating above 55 °C — suitable for unheated enclosures or outdoor cabinets in temperate climates. Pollution degree 3 and overvoltage category III are typical for fixed-installation industrial panels.