DC-rated MCB for control and auxiliary circuits
It interrupts DC faults up to 10 kA at 220 V DC per IEC 60947-2 — that 10 kA SCCR means it can safely clear a hard short on a 220 VDC bus without welding contacts or cascading upstream. At 18 mm wide (1 width unit), it snaps onto a DIN rail via the quick-assembly system and accepts conductors from 0.75 to 35 mm² solid or stranded at the combined top/bottom terminals. Terminal torque spec is 2.5–3.5 N·m (22–31 lbf·in) — hit that range; under-torquing on 35 mm² DC feeds creates a hot joint.
DC arc extinction matters — this one has it
Unlike an AC-rated MCB pressed into DC service, the 5SY5113-7CC is purpose-designed for DC voltage. DC arcs don't self-extinguish at zero-crossing, so the breaker's arc chamber and contact geometry are built for that. The 10 kA interrupting rating at 220 V DC is the real number to spec against — if your DC bus can deliver more fault current, this breaker won't hold. Overvoltage category III means it's rated for fixed-installation distribution panels, not just downstream equipment.
Ambient range -25 to +55 °C operating, -40 to +75 °C storage. Humidity tolerance up to 95% at 55 °C, derating above that. Sealable (can be locked in OFF position) for lockout/tagout compliance.