What this MCB delivers — and what the ratings mean for your panel
The Siemens 5SY4130-7 is a 1-pole miniature circuit breaker from the SENTRON family, designed for branch-circuit protection in industrial and commercial panels. Its C-curve tripping characteristic (magnetic release between 5 and 10 × In) makes it the standard choice for moderate inrush loads — motor starters, contactor coils, small transformers — where a B-curve would nuisance-trip on startup but a D-curve would delay too long for sensitive downstream equipment. Breaking capacity is the headline selection parameter here. The 5SY4130-7 carries 10 kA per IEC/EN 60898-1 and 20 kA per IEC 60947-2 — that second figure is the one that governs when the breaker is installed in an industrial panel with a high-fault transformer upstream. At 400 V AC (rated operating voltage), 20 kA SCCR means it can safely interrupt a fault current up to that level without welding contacts or cascading failure to upstream devices. For DC circuits, it's rated 15 kA at 60 V (max 72 V) per IEC 60947-2, which covers most 48 V and 60 V control buses. Under UL 1077 and CSA C22.2 No. 235, the breaker is listed for 5 kA — a supplementary protector rating, not a branch-circuit rating per UL 489. That matters for North American panel designs: it can be used as a supplementary overcurrent device within an assembly already protected by a UL 489 branch breaker.
Mounting and integration — fits a standard DIN rail slot
Width is 18 mm (1 modular unit), so it occupies one slot on a 35 mm DIN rail. The quick-assembly fastening system means it snaps on and off without tools — useful when populating a row of breakers in a panel. Mounting position is any orientation, so vertical busbars or horizontal subpanels are both fine. Installation depth is 70 mm; overall depth is 76 mm including the actuator. Combined terminals top and bottom accept copper conductors; the breaker is sealable for anti-tamper applications. IP20 with connected conductors — standard for enclosed panel mounting. Not rated for washdown; keep it inside a cabinet. Pollution degree 3 means it's designed for the conductive-dust and humidity environment typical of industrial floors.
Environmental and compliance notes
Halogen-free and silicon-free — relevant for clean-room or high-reliability environments where outgassing from a fault could contaminate optics or contacts. Temperature range spans -40 °C to 75 °C, with a derating curve for humidity: max 95% RH at 55 °C, dropping to 35% at 75 °C. Energy limitation class 3 means it limits let-through energy to a low level, reducing arc-flash risk downstream.