The 250 A rating holds continuously at 40 °C through 50 °C without derating; at 55 °C it steps down to 243 A, and at 70 °C it's still good for 223 A, so it handles warm enclosures without a frame-size jump. Breaking capacity is the headline number for this class: 121 kA at 415 V, 187 kA at 240 V, 75.6 kA at 440 V, 30 kA at 500 V, and 17 kA at 690 V.
Integration and footprint
The 3VA1225-5GE42-0AA0 measures 158 mm high, 140 mm wide, 70 mm deep — a 4-pole MCCB that fits standard panel-mount cutouts. IP40 on the front keeps dust out of the toggle and trip-indicator area; the rest of the body is open to the enclosure for heat shedding. If you need those auxiliaries, you're looking at a different 3VA order code with the appropriate suffix.