The 5SY7440-8CC: Breaking capacity is 15 kA per IEC 60947-2, which covers most industrial panel feeder and branch-circuit fault levels. For UL 1077 / CSA C22.2 No. 235 listed applications, the interrupting rating is 5 kA — check your SCCR study if the installation is North American. The D-curve means this MCB is sized for loads with high inrush — motor starters, transformers, discharge lighting — where a B or C curve would nuisance-trip on startup. The 40 A rating at 35 °C derates to 37.8 A at 40 °C, 36.64 A at 45 °C, 35.44 A at 50 °C, and 34.2 A at 55 °C; plan your continuous load against the panel ambient, not the shelf rating.
DIN-rail fit and panel integration
Occupies 4 modular width units (72 mm wide, 90 mm tall, 76 mm deep, 70 mm installation depth). Mounts in any position via the quick-assembly fastening system — standard DIN rail. The IP20 rating (with connected conductors) is typical for enclosed panel gear; not for wet or washdown locations. Combined terminal at top and bottom, touch-protected. Neutral conductor is not switched (4-pole with solid neutral). Sealable, halogen-free, silicon-free — suitable for food-and-bev or clean-room panel specs where outgassing matters.
Environmental and compliance
Rated for ambient -40 °C to 75 °C, overvoltage category III, pollution degree 3. Vibration resistance per IEC 60068-2-6: ±1 mm at 5–25 Hz, 50 m/s² at 25–150 Hz. Humidity limits: max 95 % up to 55 °C, 55 % up to 70 °C, 35 % up to 75 °C.