The Siemens 5SY4363-8 is a 3-pole D-curve miniature circuit breaker in the SENTRON line, built for industrial panels and equipment. It carries a dual interrupting rating — 10 kA under EN 60898-1 and 15 kA under IEC 60947-2 — giving you headroom for high-fault installations. The D-curve handles the inrush of motor starters and lighting transformers without nuisance tripping. Rated for AC 400/440 V and DC 72 V, it covers both main feeder and control circuit isolation. The housing is halogen- and silicon-free, and the IP20 rating with connected conductors suits panel mounting in dry environments. Pollution degree 3 and overvoltage category III let it sit upstream in industrial distribution without derating worry.
Mounts on a 35 mm DIN rail using the quick assembly system — no tools needed to snap it into the enclosure. Three modular width units (54 mm) and 76 mm depth fit standard panel layouts. Terminal top and bottom accept combined conductors, and the neutral is fixed (no moving neutral contact).
Certified to IEC/EN 60898-1, IEC/EN 60947-2, and UL 1077; the UL break rating is 5 kA, while IEC 60947-2 gives 15 kA. Operating range -40 °C to +75 °C with derating above 55 °C.