The Siemens 5SY6105-7CC is a 1-pole SENTRON miniature circuit breaker with a C tripping characteristic, rated 6 kA breaking capacity per EN 60898 at 400 V AC. This is the standard MCB for branch-circuit protection in industrial control panels — the C-curve handles moderate inrush from motor starters and contactor coils without nuisance tripping, while the 6 kA rating covers most 400 V distribution boards in commercial and light industrial installations. The 18 mm width (1 MW unit) snaps onto a DIN rail; the quick-assembly system and combined top/bottom terminals simplify busbar connection in multi-pole groups.
What the Ratings Mean for Fit
The C-curve means magnetic trip occurs at 5–10× rated current — suited for circuits with transformer inrush or motor starting, not for purely resistive loads where a B-curve would suffice. The 6 kA breaking capacity per EN 60898 is the IEC standard for residential and commercial MCBs; the UL 1077 rating of 5 kA covers North American supplementary protection applications — important if the panel ships to a UL 508A shop. Pollution degree 3 and overvoltage category III confirm it is rated for fixed installations inside an enclosure, not for outdoor or wet locations. The IP20 rating with connected conductors means the terminals are finger-safe only when wired — standard for DIN-rail gear inside a locked panel.
Integration Notes
Mounts in any position on a DIN rail. Installation depth is 70 mm, overall depth 76 mm — factor that into enclosure depth if using a shallow gland plate. The 18 mm width occupies one modular unit; combined top and bottom terminals accept busbar links for daisy-chaining phases. Sealable — the toggle can be locked in the OFF position for lockout/tagout. Halogen-free and silicon-free construction avoids corrosive off-gassing in sealed enclosures near sensitive electronics.