Siemens 5SY4663-8CV is a 4-pole miniature circuit breaker (3+N, neutral switched) with D-curve tripping characteristic, rated 63 A at 35 °C ambient per IEC 60947-2. The D-curve (10–20× In magnetic trip) is sized for motor-starting inrush and high-inductive loads — a standard choice for conveyor drives, compressors, and pump panels where the instantaneous trip must ride through the start surge without nuisance opening. At 440 V AC (multi-phase operation) the same 15 kA holds — no derating at the higher voltage. Temperature derating is published: 59.54 A at 40 °C, 57.71 A at 45 °C, 55.8 A at 50 °C, 53.86 A at 55 °C.
Mounting and integration — DIN-rail quick-assembly
Occupies 4 modular-width units (72 mm width). Installation depth 70 mm; overall depth 76 mm with terminals. Rated for pollution degree 3 (conductive dust or humidity) and overvoltage category III (distribution level). Sealable cover option for panel lockout.
Lifecycle and compliance — current production, full documentation
Designed to IEC / EN 60947-2 (not the household EN 60898 standard), which means it is rated for industrial coordination and higher fault currents. Halogen-free and silicon-free construction. Vibration resistance per IEC 60068-2-6: ±1 mm at 5–25 Hz, 50 m/s² at 25–150 Hz.