What this MCCB carries
The Siemens SENTRON 3VA1225-6EF32-0AB0 is a 3-pole molded case circuit breaker rated for 250 A continuous current (Iu) with a TM240 thermal-magnetic overcurrent release. That TM240 designation means the thermal trip is fixed at 250 A and the magnetic short-circuit pickup is adjustable — you set the instantaneous trip threshold to coordinate downstream. The 220 kA breaking capacity at 240 V is the headline number for most panel builders, but the 154 kA at 415 V and 36 kA at 440 V are the real-world figures for 400 V-class distribution. At 690 V it still clears 17 kA, which covers most motor-circuit fault levels in industrial plants.
Thermal derating and panel fit
This breaker holds its full 250 A rating up to 50 °C ambient. Above that it derates linearly: 243.3 A at 55 °C, 236.5 A at 60 °C, 229 A at 65 °C, and 223 A at 70 °C. If your panel ambient runs hot — say a sealed enclosure near a furnace line — that 223 A floor at 70 °C still leaves headroom for a 200 A continuous load. The 105 mm width and 158 mm height are standard SENTRON 3VA frame dimensions; the 70 mm depth means it clears most 200 mm-deep enclosures with room for the rear arc chamber. IP40 on the front face keeps out tool drops and dust, but the body itself is open-frame — mount it where condensation or washdown spray won't reach the sides.
Sourcing and cross-reference
This is a current-production SENTRON 3VA frame breaker, so supply runs through normal Siemens distribution. The closest functional sibling in the same family is the 3VA1010-2ED32-0JA0 — that's a 100 A frame with a different thermal-magnetic release and lower interrupting ratings. It won't drop into a panel wired for 250 A without re-cabling and re-sizing the bus bars. If you're holding a BOM that calls out this 3VA1225-6EF32-0AB0, the fit is locked to the 250 A frame and the TM240 release curve; the 3VA1010 is a different animal for a different load.