63 A MCCB with flat thermal derating and onboard comms
The Siemens SENTRON 3VA2163-8KQ32-0AA0 is a 3-pole molded case circuit breaker rated for 63 A continuous current, designed for line protection in distribution panels. Its interrupting capacity reaches 440 kA at 240 V, 330 kA at 415 V, and 52.5 kA at 690 V — per the datasheet, the full-scale value is 63 A with a minimum setting of 95 A and maximum of 756 A. What sets this MCCB apart is the flat derating curve: the 63 A rating holds from 40 °C through 70 °C ambient, with no reduction at 65 °C or 70 °C. That means in a tightly packed enclosure or near heat sources, you don't lose ampacity — the breaker delivers its full 63 A across the operating range of -25 °C to 70 °C. The unit includes a communication function and ground-fault monitoring via summation current formation on the L-conductor, making it suitable for integration into monitored distribution systems. Rated insulation voltage is 800 V, and maximum power loss is 3.1 W.
Panel fit and mounting dimensions
Physical footprint is 86 mm depth by 105 mm width by 181 mm height (3.39 x 4.13 x 7.13 inches). The 105 mm width for a 3-pole MCCB is standard for Siemens SENTRON frames — it occupies three modular 35 mm DIN spaces, so it drops into existing SENTRON panel layouts without re-drilling gland plates or re-spacing busbars.