What this MCCB carries
The Siemens SENTRON 3VA2225-6HN32-0DH0 is a 3-pole molded case circuit breaker rated 250 A continuous at 40 °C, with an ETU350 electronic trip unit for line protection. Its interrupting capacity hits 242 kA at 240 V and 187 kA at 415 V — numbers that tell you it'll clear a hard fault without the arc climbing upstream. The front face carries IP40 protection, so it's fine inside a clean panel but not for washdown areas. An undervoltage release (UVR) is built in, and the auxiliary contact block comes as 2 auxiliary switches plus 1 trip alarm switch (HQ version). That alarm switch closes when the breaker trips, giving you a positive signal for a PLC or annunciator — handy for fault isolation out here in the grease.
Dimensions and panel fit
The breaker measures 181 mm high, 105 mm wide, and 86 mm deep. That 105 mm width is the standard 3-pole MCCB footprint for this class — it'll drop into a panel that was laid out for a SENTRON 3VA frame without re-drilling the gland plate. The 86 mm depth leaves room behind the door for wiring gutters.
Thermal derating you need to know
The breaker is rated 250 A from 40 °C up to 50 °C. At 55 °C it derates to 241 A, at 60 °C to 232 A, and at 70 °C to 213 A. If your panel runs hot — say near a drive stack or a sunny roof — size your load against the 70 °C figure, not the 40 °C number. The maximum operating temperature is 70 °C; storage can go from -40 °C to 80 °C.