What this MCCB carries
The Siemens 3VA2463-5JQ32-0AA0 is a SENTRON molded case circuit breaker rated for 630 A continuous at 40 °C, with a maximum breaking capacity of 187 kA at 240 V. That 187 kA figure drops to 121 kA at 415 V and 440 V, then 75.6 kA at 500 V, and 9 kA at 690 V — so the real-world SCCR you spec depends on your system voltage, not the headline number. The trip unit is adjustable between 945 A minimum and 5670 A maximum, giving you selectivity headroom downstream. This is a 3-pole design built for line protection, with a communication function onboard — no separate module needed for basic connectivity. The insulation voltage is rated 800 V, so it handles 690 V systems without derating the dielectric.
Thermal derating and panel fit
The 630 A rating is at 40 °C ambient. At 45 °C it carries 600 A, at 50 °C it's 570 A, and it steps down to 450 A at 70 °C. If your panel runs hot — say a packed enclosure with drives — you need to pick the derated value, not the catalog number. The frame dimensions are 248 mm tall, 138 mm wide, 110 mm deep, which is the standard 3VA3 frame size; it bolts into a panel cutout sized for that footprint. Maximum power loss is 162 W. That's the heat you have to vent through the enclosure — factor it into your thermal budget, especially if the MCCB sits next to other high-current devices.
What the ratings mean for your BOM
Minimum trip setting is 945 A. This breaker suits a main or large feeder. For loads under 600 A, a smaller frame like the 3VA1 series may be a tighter fit.