What this MCCB carries — and where it fits
The Siemens 3VA1225-6EF32-0AD0 is a 3-pole SENTRON molded case circuit breaker rated for 250 A continuous current with a TM240 thermal-magnetic release. Its interrupting capacity hits 220 kA at 240 V and 154 kA at 415 V — numbers that tell you it belongs in high-fault panels like main switchboards, transformer secondaries, or large motor control centers where a standard MCCB would weld shut on a bolted fault. The 105 mm width and 70 mm depth keep it within a standard 600 mm panel depth without forcing a deeper enclosure.
Thermal-magnetic curve and derating
The TM240 release is a fixed thermal-magnetic trip — no interchangeable trip unit, no electronic adjustment. That means the breaker is sized for a specific load and stays there. At 40 °C through 50 °C it holds full 250 A; at 55 °C it derates to 243.3 A, at 65 °C to 229 A, and at 70 °C to 223 A. If your panel ambient runs hot, factor that curve into the conductor sizing.
Panel integration and wiring
The breaker mounts with a fixed three-pole footprint. It carries three auxiliary switches (HQ type) for status feedback back to a PLC or annunciator — useful for remote trip indication since the breaker itself has no local trip indicator. The front face is IP40, so it's fine inside a closed panel but not rated for washdown or outdoor exposure. Rated insulation voltage is 800 V, covering most 480/600 V distribution systems. Operating temperature range is -25 °C to 70 °C, storage from -40 °C to 80 °C.