What the ratings mean for your panel
The Siemens 5SY6308-7CC is a 3-pole SENTRON miniature circuit breaker with a C tripping characteristic, rated 8 A at 35 °C and 6 kA breaking capacity per EN 60898. It protects branch circuits against overload and short-circuit in industrial control panels, distribution boards, and machinery — the C-curve (5–10× In) handles moderate inrush from motor starters and small transformers without nuisance tripping. At 40 °C ambient the continuous rating derates to 7.35 A, at 45 °C to 7 A, at 50 °C to 6.63 A, and at 55 °C to 6.25 A — so if the panel runs hot, size the upstream load accordingly. The breaker is rated for overvoltage category III and pollution degree 3, meaning it's suited for fixed installations inside an enclosure where transient overvoltages and conductive dust are expected. Snaps onto DIN rail via the quick-assembly system and fits any mounting position. At 3 modular width units (54 mm wide, 76 mm deep, 90 mm high) it occupies three 18 mm slots in the distribution board. The combined top and bottom terminals accept conductors with IP20 protection once wired.