6 A, Class A — what the ratings mean for the panel
The 5SY4306-5 is a 3-pole miniature circuit breaker from the Siemens SENTRON family, rated 6 A at AC. The Class A tripping characteristic means it trips on overload between 2 and 3 times rated current — tighter than a B-curve, so it catches moderate overcurrents faster while still allowing brief inrush from resistive loads like heaters or lighting banks. Breaking capacity is 10 kA per EN 60898 and 35 kA per IEC 60947-2. The 35 kA figure applies when the breaker is installed per the industrial standard — useful for high-fault locations near transformers or large motor banks where the prospective short-circuit current exceeds 10 kA.
Temperature derating — don't size by the 35 °C number alone
The 6 A rating holds at 35 °C ambient. At 40 °C it derates to 5.71 A, at 50 °C to 5.41 A, and at 60 °C to 5.09 A. In a crowded DIN rail enclosure with multiple breakers side by side, the internal ambient can easily hit 50 °C — size the upstream protection for the derated value, not the nameplate. Operating range spans -40 °C to 75 °C, with humidity limits of 95% RH up to 55 °C and 35% RH at 75 °C. The breaker is halogen-free and silicon-free, which matters for clean-room or coated-board environments where outgassing can contaminate contacts.
DIN rail fit and panel integration
Width is 54 mm — three modular units on a standard DIN rail. Depth is 76 mm, installation depth 70 mm. The quick-assembly fastening method snaps onto the rail without tools; mounting position is any orientation. IP20 with connected conductors — the terminals are touch-safe once wired, but the breaker itself is not sealed against dust ingress. Overvoltage category III and pollution degree 3 suit it for fixed installations in industrial panels where transient overvoltages from switching loads are common.
Sourcing and lifecycle
Standards compliance includes IEC/EN 60898-1, IEC/EN 60947-2, and UL1077. The UL1077 listing means it is recognized as a supplementary protector in North American panels, not a branch-circuit rated breaker — confirm the application's UL listing requirement before specifying.