The Siemens SENTRON 5SP3763-2KK02 is a 1-pole miniature circuit breaker (MCB) with an E-tripping characteristic, rated 63 A at 230 V AC and 50 Hz. It's built for residential and infrastructure panels — think meter cabinets, distribution boards, and building supply circuits where you need a higher inrush tolerance than a B-curve but faster response than a D-curve.
This breaker snaps onto a 40-mm busbar system per DIN 43870 Part 2 — the standard meter-panel layout in European installations. At 1.5 width units (modular), it's wider than a standard single-module MCB, so check your DIN-rail or busbar comb spacing before committing. The enclosure depth is 76.3 mm; overall depth with terminals is 89.5 mm. Infeed is at the box terminal; outgoing is via a spring-loaded terminal that accepts solid or stranded copper from 2.5 to 50 mm².
What the E-curve and ratings mean on the job
The E-tripping characteristic sits between the classic C and D curves — it allows a short-duration inrush of 10 to 20 times rated current before the magnetic trip fires. The 63 A rating carries the continuous load; the 25 kA rated short-circuit capacity (at 230 V AC) means it can safely interrupt a fault up to 25,000 amps without welding its contacts or bursting the case.
Environmental and handling limits
Shock-rated to 30 g (11 ms pulse, 3 impacts) and vibration-tested to 2 g per IEC 60068-2-6, so it'll hold up in a genset enclosure or a panel bolted to a machine skid. The switch-position indicator shows green for ON, red for OFF — no guessing when you're trying to confirm isolation.