63 A D-curve MCB for high-inrush loads
The Siemens 5SL4663-8 is a SENTRON miniature circuit breaker rated 63 A with a D tripping characteristic, 3P+N (4-pole) construction, and a 400 V AC supply voltage. The D-curve is designed for loads with high inrush currents — motor starters, transformers, welding equipment — where a C-curve would nuisance-trip on startup. The 10 kA breaking capacity is certified to both EN 60898 and IEC 60947-2, meaning it can safely interrupt faults up to 10 kA at 400 V AC without cascading upstream. At 72 mm wide (4 modular width units), this breaker occupies four standard DIN-rail slots. The IP20 rating with connected conductors is typical for enclosed panel mounting.
Panel fit and compliance
Mounting position is any — no derating needed for horizontal or vertical orientation. The 76 mm depth and 70 mm installation depth fit standard distribution board enclosures. Sealable design allows lockout/tagout. Supplementary devices (auxiliary contacts, shunt trips, alarm switches) can be added via the product extension interface. Halogen-free and silicon-free construction meets material compliance requirements for infrastructure projects. The breaker is rated for DC circuits up to 72 V maximum.