630 A continuous, 187 kA at 240 V — this is the interrupting muscle for main feeders
The Siemens 3VA2463-5HM32-0KJ0 is a 3-pole SENTRON molded case circuit breaker rated for 630 A continuous at 40 °C, with a thermal derating curve that drops to 520 A at 70 °C — a straight line the panel designer can bank on for enclosure sizing. The adjustable trip unit spans 945 A minimum to 5670 A maximum, so this breaker is set up as a main or heavy feeder device, not a branch-level component. Short-circuit interrupting capacity hits 187 kA at 240 V, 121 kA at 415/440 V, and still holds 75.6 kA at 500 V; only at 690 V does it drop to 9 kA, which keeps it on the 480 V class switchboard side of the arc-flash boundary.
What the ratings mean for the panel designer
The 630 A frame at 40 °C is the continuous current the main bus must carry without exceeding the breaker's internal rise limits. Below 40 °C you get no upside — the rating is fixed at the 40 °C mark. Above 40 °C the derate is linear: 612 A at 45 °C, 593 A at 50 °C, 575 A at 55 °C, 557 A at 60 °C, 538 A at 65 °C, 520 A at 70 °C. If the enclosure ambient hits 50 °C, the breaker effectively becomes a 593 A device; don't load the bus to 630 A and expect the trip unit to hold. The 187 kA at 240 V tells you this breaker can clear a bolted fault on the secondary side of a 1500 kVA transformer without external current-limiting fuses — useful for utility entrance gear where the available fault current is high. Auxiliary switch complement is 2 form-C aux contacts plus 1 trip alarm switch, which is enough for status feedback to a PLC and a separate alarm annunciator without adding a third accessory.
Environmental and auxiliary release details
Operating temperature range is -25 °C to +70 °C; storage range is -40 °C to +80 °C. The breaker includes a shunt trip release (STL) for remote tripping — useful for emergency-stop circuits or supervisory shutdown. No undervoltage release is fitted on this variant. Maximum power loss at rated current is 162 W, which goes into the enclosure thermal calculation. The trip indicator and voltage trigger are present, so the breaker can signal a trip condition externally without relying on the aux switch alone.