630 A MCCB with 330 kA interrupting capacity — selectivity and SCCR headroom
The Siemens SENTRON 3VA2463-7HN32-0AE0 is a 3-pole molded case circuit breaker rated 630 A continuous at 40 °C, with a 330 kA interrupting capacity at 240 V. That interrupting rating drops to 242 kA at 415 V and 440 V, 187 kA at 500 V, and 52.5 kA at 690 V — so for a 480 V panel the available fault current must stay under 187 kA to maintain full coordination. The ETU350 electronic trip unit provides adjustable long-time, short-time, instantaneous, and ground-fault protection curves, which means you can shape the trip response to coordinate with downstream breakers rather than relying on a fixed thermal-magnetic curve.
Thermal derating — the real ampacity in a warm panel
The 630 A rating holds at 40 °C ambient. At 45 °C it derates to 612 A, at 50 °C to 593 A, at 55 °C to 575 A, at 60 °C to 557 A, at 65 °C to 538 A, and at 70 °C to 520 A. If this breaker sits in a non-air-conditioned enclosure near transformers or drives, the 70 °C figure (520 A) is the one to size against — the 630 A nameplate is only valid in a 40 °C environment.
Physical fit and panel integration
Dimensions are 248 mm high, 138 mm wide, and 110 mm deep. The 138 mm width is standard for a 3-pole frame at this rating — it fits the same cutout as other 630 A SENTRON frames. IP40 on the front means it is protected against tools and wires >1 mm entering the front face, but the rear and sides are open for panel mounting; no IP rating for washdown environments. The basic switch variant is 3VA2463-7HN32-0AA0, and the integrated auxiliary trip is 3VA9608-0BB24 — these are the sub-assembly order codes if you are rebuilding rather than replacing the complete breaker.