What this MCB is and where it fits
The Siemens 5SY6180-7CC is a 1-pole miniature circuit breaker from the SENTRON family, rated 80 A at AC with a C tripping characteristic. It is designed for branch-circuit protection in industrial control panels and distribution boards, snapping onto DIN rail and occupying a single 18 mm modular width. The C-curve means it trips between 5 and 10 times rated current — suited for loads with moderate inrush, like small motors, contactor coils, or lighting banks, where a B-curve would nuisance-trip but a D-curve would delay too long. Breaking capacity is 6 kA per IEC 60947-2 and 5 kA per UL 1077 / CSA C22.2 No.235 — enough for most secondary distribution panels where the upstream transformer limits fault current below those levels. The 6 kA IEC rating is the one that governs selectivity coordination in European-style panels; the 5 kA UL figure tells you it passes North American supplementary protector testing, so it can serve as a branch-circuit protective device in UL 508A industrial control panels.
Thermal derating and real-world current
The 80 A rating holds at 35 °C ambient. At 40 °C it derates to 75.2 A; at 45 °C to 72.72 A; at 50 °C to 70.08 A; at 55 °C to 67.36 A. If the panel ambient runs hot — say a sealed enclosure near a process line — use the 40 °C or 50 °C column to size the load so the bimetal strip doesn't trip prematurely. The breaker also carries a humidity derating curve: max 95 % RH up to 55 °C, then 55 % to 70 °C, then 35 % to 75 °C. That matters in washdown or outdoor cabinets where condensation cycles are common.
Physical fit and installation
Dimensions: 18 mm wide, 90 mm high, 76 mm deep. Installation depth is 70 mm behind the panel face. It snaps onto DIN rail via the quick-assembly system and can be mounted in any position. The combined terminals at top and bottom accept conductors for both busbar and cable — no separate feed-through lug needed. Pollution degree 3 (conductive pollution, or dry non-conductive that becomes conductive under condensation) and overvoltage category III mean it's rated for fixed installation inside the building envelope, not just clean-room switchgear.
Compliance documentation
The 5SY6180-7CC is halogen-free and silicon-free — relevant for environments where outgassing can contaminate optics or sensitive electronics. It carries touch protection on the terminals. The product is designated per IEC 81346-2 and DIN EN 61346-2 as function code F (protective device). No RoHS/REACH certificate is in this evidence set, but the brand standard for SENTRON MCBs is full compliance with EU directives; request the declaration at quote time if your compliance audit requires it.