D-Curve Trip — Built for High-Inrush Loads
The 5SY4350-8: The D tripping characteristic means this breaker holds through the magnetizing inrush of transformers, solenoid banks, and small motor starters without nuisance tripping — the magnetic release threshold sits around 10–20× rated current, well above the C-curve range. Rated 400 V AC for multi-phase operation, 60 V DC per pole — the DC rating drops because the arc extinguishes differently without a zero-crossing. Breaking capacity is 10 kA per EN 60898-1 for general distribution, 15 kA per IEC 60947-2 for industrial panel duty — that extra 5 kA matters when the transformer fault current is higher than the domestic standard.
Panel Fit and Environmental Range
Three modular width units (54 mm wide) on standard DIN rail — the quick-assembly system clips on without tools and the supply can land on either end. Depth is 76 mm, installation depth 70 mm — leaves clearance for wiring gutters in a 200 mm deep enclosure. Ambient range -40 °C to 75 °C with humidity derating: max 95% RH at 55 °C, dropping to 35% at 75 °C — the plastic housing and internal bimetal track the moisture limits. IP20 with conductors connected — not sealed for washdown, but fine for dry indoor panels.
Certification and Compliance Package
Dual-rated to IEC/EN 60898-1 (domestic/similar) and IEC/EN 60947-2 (industrial) plus UL 1077 — covers most global panel specs without a second breaker. Halogen-free and silicon-free construction — important for clean-room or corrosive-environment panels where outgassing contaminates contacts or optics. Vibration tested per IEC 60068-2-6: ±1 mm at 5–25 Hz, 50 m/s² at 25–150 Hz — holds up on machine-mounted enclosures near rotating equipment. Sealable — the toggle can be locked in the off position for lockout/tagout compliance.