What this MCCB is and what it does
The Siemens 3VA1112-3EF32-0KA0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries a 125 A continuous rating at 40 °C ambient, with a thermal-magnetic TM240 overcurrent release that handles both overload and short-circuit conditions. The 3-pole unit breaks up to 75.6 kA at 240 V, 52.5 kA at 415 V, and 32 kA at 440 V — figures that govern its fault-clearing capability in a given system voltage. Rated insulation voltage is 800 V, so it can be applied in 480/277 V and 600 V panels with headroom. The shunt trip (STL) auxiliary release allows remote tripping, useful for emergency-stop or interlock circuits. Power loss at rated current is 28.1 W — a figure to factor into enclosure thermal calculations.
Integration and mounting
The 3VA1112-3EF32-0KA0 mounts on a DIN rail or panel-mount baseplate. Dimensions are 130 mm height, 76.2 mm width, and 70 mm depth — a standard SENTRON 3VA footprint that fits existing distribution board cutouts. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C.