630 A MCCB for main feeder or large motor protection
The Siemens 3VA2463-6JP32-0CA0 is a SENTRON molded case circuit breaker rated for 630 A continuous current, sized for main incoming feeders or large motor branch circuits in industrial switchboards. The 3-pole design handles three-phase loads up to 630 A, with a breaking capacity that starts at 242 kA at 240 V and holds 187 kA through 440 V before dropping to 121 kA at 500 V and 9 kA at 690 V — so at typical 400/415 V distribution voltages it clears faults well above most utility transformer ratings. The unit ships with an undervoltage release (UVR) integrated, meaning it will trip if supply voltage drops below a set threshold — useful for preventing motor re-acceleration after a sag or for coordinating with emergency-stop circuits that kill control power. Communication function is onboard, so it can report status and trip events to a PLC or BMS without an add-on module.
Derating and thermal management in the panel
The 630 A rating holds at 40 °C ambient; above that, the breaker must be derated: 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 the panel ambient runs hot — say next to a drive cabinet or in a non-conditioned enclosure — the actual load current must stay under the derated figure, not the nameplate 630 A. The maximum power loss is 164.5 W, which needs to be considered in the enclosure thermal calculation. Dimensions are 110 mm deep, 138 mm wide, 248 mm tall — a standard MCCB footprint that fits most DIN-rail or panel-mount arrangements in 600 V switchgear. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C.