Siemens 5SY6305-7 — SENTRON 3-Pole MCB, C-Curve, 0.5 A
Rated breaking capacity is 6 kA per EN 60898-1 and 30 kA per IEC 60947-2 / UL1077. Thermal derating is published: 0.5 A at 35 °C, 0.48 A at 40 °C, 0.46 A at 45 °C, 0.45 A at 50 °C, 0.44 A at 55 °C. For a panel that runs warm (say 50 °C inside the enclosure), the effective continuous current is 0.45 A — not 0.5 A. The ambient humidity limits are also specified: max 95% RH up to 55 °C, derating to 35% RH at 75 °C.
Depth is 76 mm (installation depth 70 mm), width 54 mm (3 MW), height 90 mm. The combined terminal design (top and bottom) accepts conductors without separate busbar adapters for most configurations. Neutral conductor switching is not provided; this is a 3-pole breaker for line switching only, with neutral assumed solidly bonded or switched separately.
Certified to IEC / EN 60898-1 (domestic/commercial MCB standard) and IEC / EN 60947-2 / UL1077 (industrial circuit-breaker standard). The dual rating means it can be specified for either a residential-type distribution board (6 kA) or an industrial panel with higher fault capacity (30 kA). Energy limitation class 3 — limits let-through energy during a fault, reducing stress on downstream components. The part carries the function designation F per both EN 61346-2 and IEC 81346-2.