What this MCCB carries and where it fits
The Siemens SENTRON 3VA2463-6KP32-0KH0 is a 3-pole molded case circuit breaker rated for 630 A continuous current at 40 °C, with an ETU850 electronic trip unit and a 242 kA interrupting capacity at 240 V. That breaking capacity drops as voltage rises — 187 kA at 415 V and 440 V, 121 kA at 500 V, and 40 kA at 690 V — so it handles high-fault utility feeds and transformer secondaries without cascading upstream. The 110 mm depth and 138 mm width fit standard MCCB panel cutouts; the 248 mm height leaves room for auxiliary wiring above the line lugs. This is a line-protection version, meaning it's configured for feeder and main breaker duty — not motor circuit protection with integral overloads. The ETU850 release gives you adjustable long-time, short-time, instantaneous, and ground-fault curves, plus a communication function for remote monitoring and another measurement function for energy data. The shunt trip (STL) auxiliary release lets you add remote tripping via a control signal. Auxiliary contacts come as two auxiliary switches plus one trip alarm switch HQ.
Thermal derating and endurance
The 630 A rating is at 40 °C ambient. Above that, the breaker derates linearly: 600 A at 45 °C, 570 A at 50 °C, 540 A at 55 °C, 510 A at 60 °C, 480 A at 65 °C, and 450 A at 70 °C. If your panel enclosure runs hot — say 50 °C internal ambient — you lose about 10% of the continuous rating. Factor that into your load schedule. The mechanical endurance is 15,000 operations, which is typical for a distribution MCCB; not a switching-duty device, but fine for infrequent on-load switching and fault clearing. Operating temperature range spans -25 °C to 70 °C. Storage range goes from -40 °C to 80 °C. The 162 W maximum power loss at full load means the breaker dissipates heat into the enclosure — account for that in your panel thermal design, especially in a sealed cabinet.