What this MCCB carries
The Siemens SENTRON 3VA1225-5EF42-0AJ0 is a 4-pole molded case circuit breaker rated 250 A continuous at 40 °C, with a TM240 thermal-magnetic overcurrent release. That 250 A holds flat through 50 °C; above that it derates to 243 A at 55 °C and 223 A at 70 °C, so in a warm panel you still have headroom for a full 250 A load up to 50 °C ambient. Interrupting capacity is 187 kA at 240 V, 121 kA at 415 V, and 75.6 kA at 440 V — numbers that put it in the high-fault tier for a 250 A frame. Rated insulation voltage is 800 V, so it's comfortable on 480 V or 600 V class systems. Power loss runs 57 W maximum at rated current — figure that into your enclosure thermal budget if the panel is tightly packed.
Panel fit and integration
Dimensions are 158 mm high, 140 mm wide, 70 mm deep — a 4-pole frame that fits standard SENTRON mounting plates and busbar systems. The 70 mm depth is shallow enough for most 200 mm deep enclosures with room for wiring gutters. It ships with 2 auxiliary switches plus 1 trip alarm switch (HP type) built in, so you get remote status without adding a separate accessory module. No undervoltage release, no ground-fault monitoring — this is a straight line-protection breaker.