Siemens 5SN6303-7CP — SENTRON 3-Pole MCB, C-Curve
The Siemens 5SN6303-7CP is a 3-pole miniature circuit breaker from the SENTRON 5SN family, rated for 400 V AC at 50 Hz with a C tripping characteristic. Its breaking capacity is 6 kA per EN 60898 and 30 kA per IEC 60947-2 — the higher IEC figure governs industrial panel coordination where fault current can exceed 10 kA. The 3-pole construction handles three-phase loads up to 440 V AC maximum.
The 90 mm height keeps it aligned with adjacent SENTRON devices in a multi-row enclosure. Terminals accept solid conductors up to 35 mm², sufficient for downstream feeder wiring in a sub-distribution board. Power loss per pole is 1.3 W in hot operating state — factor this into enclosure thermal calculations when grouping multiple breakers.
Environmental Range and DC Capability
On the DC side, it handles up to 72 V — useful for control-circuit protection in the same enclosure.