Line protection MCCB with UVR and aux switches
The Siemens SENTRON 3VA2063-6HL32-0BH0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection duty. It carries a continuous current of 63 A with no derating across the ambient range from 40 °C up to 70 °C — all entries show 63 A flat, so the thermal curve buys you headroom in a warm panel. Breaking capacity runs 242 kA at 240 V, 187 kA at 415/440 V, 121 kA at 500 V, and 3 kA at 690 V. That 242 kA figure at 240 V is the high-interrupting variant; it handles fault currents on large transformers or busway feeds without cascading upstream. The breaker ships with an undervoltage release (UVR) fitted — part of the order code suffix — plus two auxiliary switches and one trip alarm switch (HQ design). The UVR drops the breaker when control voltage falls below its dropout threshold, which is useful for emergency-stop chains or power-loss sequencing. No ground-fault monitoring on this variant; that's a separate order-code option. Dimensions are 181 mm high, 105 mm wide, 86 mm deep — standard SENTRON 3VA2 frame size. Panel cutout and DIN-rail adapter follow the 3VA family footprint; if you're swapping from a different MCCB brand, check the mounting centres against your existing backplate.
Integration notes
Mounts on DIN rail or direct panel-mount via the 3VA2 base. The 105 mm width means it occupies three 35 mm module spaces on the rail — plan your gland plate and wireway fill accordingly. Power loss at rated load is 7.9 W maximum; in a sealed enclosure with multiple breakers, that heat adds up, so factor it into your thermal budget. Storage range is -40 °C to 80 °C; operating range is -25 °C to 70 °C. The storage minimum is the handling limit — don't leave it in an unheated truck overnight in a deep freeze, but it can sit on a shelf in a cold warehouse.