What it is and what it does
The Siemens 5SY6515-7 is a SENTRON miniature circuit breaker (MCB) rated 1.6 A at AC with a C tripping characteristic, designed for branch-circuit overcurrent and short-circuit protection in industrial control panels and distribution boards. It switches both line and neutral (1P+N, 2 poles) and carries a 6 kA breaking capacity per EN 60898 and 30 kA per IEC 60947-2 / UL1077 — the higher figure applies when the part is applied under the industrial standard, so it handles fault currents up to 30 kA without upstream cascading in most panel builds.
Key ratings and what they mean for fit
Rated 1.6 A at 35 °C, derated to 1.52 A at 40 °C, 1.48 A at 45 °C, 1.44 A at 50 °C, and 1.4 A at 55 °C — the thermal derating curve is published, so a panel ambient above 35 °C reduces the continuous current the breaker can carry without nuisance tripping. The C-curve (magnetic trip between 5× and 10× In) is standard for moderate inrush loads like small motors, transformers, or lighting banks; it avoids nuisance trips on startup while still clearing a hard short. The 6 kA rating under EN 60898 covers residential and light commercial service; the 30 kA rating under IEC 60947-2 / UL1077 covers industrial installations where available fault current is higher. Pollution degree 3 and overvoltage category III mean it is rated for the harsh electrical environment inside a factory panel — not just a clean office distribution board. IP20 with connected conductors — the front is touch-safe once wired, but the breaker is not sealed against dust or moisture ingress; it belongs inside a closed enclosure, not in a washdown zone.
Mounting and integration
Snap-on DIN-rail mount, 2 modular width units (36 mm wide), 76 mm deep, 90 mm tall. Mounting position any, fastening via quick assembly system — clips onto the rail without tools. Combined terminals top and bottom accept the same conductor range; neutral is switched internally, so no separate neutral bar is needed for the outgoing circuit. Sealable (provision for a lead seal or lockout tag), halogen-free and silicon-free construction — relevant for panels in clean-room or corrosive environments where outgassing matters.