What it is and what it handles
The Siemens SENTRON 3VA1112-3EF32-0AB0 is a 3-pole molded case circuit breaker (MCCB) rated for 125 A continuous current, with a TM240 thermal-magnetic overcurrent release. Its breaking capacity hits 75.6 kA at 240 V, 52.5 kA at 415 V, and 32 kA at 440 V — numbers that tell you it's built for high-fault industrial panels, not light commercial.
What the ratings mean for your panel
The 125 A rating holds steady from 40 °C up to 50 °C, then derates gradually to 112.5 A at 70 °C — so if your panel runs hot near a motor starter or drive, you still get nearly full current without nuisance tripping. The 75.6 kA interrupting rating at 240 V means it can safely clear a bolted fault up to that level, which covers most secondary-side transformer faults in industrial plants. Rated insulation voltage Ui is 800 V, giving headroom for 690 V line-to-line systems.
Where it fits and how it mounts
The breaker measures 130 mm high, 76.2 mm wide, and 70 mm deep — a standard MCCB footprint that drops into most SENTRON panelboards or DIN-rail adapters without re-drilling gland plates. IP40 on the front means it's fine in a clean enclosure; keep it out of washdown zones unless it's behind a sealed cabinet door. Comes with 2 auxiliary switches HP built in for status feedback to a PLC or annunciator.