The Siemens SENTRON 5SL6304-7CC is a 3-pole miniature circuit breaker with a C-curve trip characteristic, rated 4 A at 400 V AC. Its 6 kA breaking capacity per EN 60898 covers standard residential and light commercial infrastructure branch circuits — think lighting panels, small distribution boards, and general-purpose power feeds where fault levels stay under that threshold. C-curve means the magnetic trip fires between 5 and 10 times rated current — 20 to 40 A for this 4 A unit. That's the right match for mixed resistive and moderate inductive loads: lighting, small motors on start-up, control transformers. It won't nuisance-trip on a motor's inrush, but it clears a hard short fast enough to protect the downstream wiring.
Sizing and thermal derating
The 4 A rating holds at 30 °C ambient. Push the panel ambient to 40 °C and you're down to 3.82 A; at 50 °C it's 3.63 A. If this breaker sits in a crowded enclosure next to other heat sources, size the load against the derated figure — not the 30 °C number. The 75 °C max operating temp is the case limit, not the load-carrying limit.
Mechanical fit and panel integration
Three modular units wide at 54 mm, 76 mm deep, 90 mm tall. Snaps onto standard DIN rail in any mounting position. The 70 mm installation depth leaves room behind the rail for wiring — no tight squeeze. Spring-cage terminals accept 0.2–2.5 mm² solid or ferruled stranded; strip length 8 mm. IP20 with conductors connected — fine inside a closed panel, not for wet or dusty locations.