What this 630 A MCCB does on the line
The Siemens 3VA2463-5KP32-0KH0 is a 3-pole SENTRON molded case circuit breaker rated for 630 A continuous at 40 °C, with an interrupting capacity of 187 kA at 240 V and 121 kA at both 415 V and 440 V. That 187 kA figure at 240 V tells you this breaker can clear a massive fault without venting or cascading upstream — it's sized for high-fault panels where the available short-circuit current is serious. The adjustable thermal-magnetic trip covers a range from 945 A minimum to 5 670 A maximum, so you dial it in to protect the feeder, not just the bus. This is a line-protection design (not a motor-protection or generator breaker), meaning it's intended for main or branch feeder duty in distribution panels. The communication function allows integration with a BMS or SCADA system for remote monitoring and trip-event capture — useful when you need to know why a feeder dropped without walking the panel.
Mounting and panel fit
At 248 mm high, 138 mm wide, and 110 mm deep, this MCCB fits a standard SENTRON mounting footprint. The 110 mm depth (4.33 in) means it clears most shallow enclosure backplates — measure your gland-plate clearance before you drill, especially on retrofit jobs where the old breaker was a different frame. The 138 mm width (5.43 in) is the three-pole envelope; if you're swapping in a panel that was laid out for a narrower frame, check the bus-bar takeoff spacing. Power loss is 162 W maximum at full load — that's heat that has to leave the enclosure. In a sealed panel with other breakers running hot, factor that into your thermal derating. The operating temperature range is -25 °C to 70 °C; storage can go from -40 °C to 80 °C, which matters if the breaker sits in an unheated warehouse before install.
Thermal derating and real-world current
The 630 A rating at 40 °C is the headline number, but if your panel runs hot — and most do — you lose current fast: 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. That's a 28% drop from 40 °C to 70 °C. If your feeder load is 500 A and the ambient inside the enclosure is 60 °C, this breaker is at its limit — you'd need to step up a frame or ventilate the panel.