MCCB with ETU850 trip unit — 250 A frame, 3-pole
The Siemens SENTRON 3VA2225-6KP32-0AG0 is a 3-pole molded case circuit breaker (MCCB) rated for 250 A continuous current (Iu) and built around the ETU850 electronic trip unit.
Current derating and thermal limits
The breaker holds its full 250 A rating from 40 °C through 50 °C ambient. Above that, derating is linear: 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C — the maximum operating temperature. If your panel ambient runs hot, factor the 55 °C+ curve into your load schedule. The rated insulation voltage is 800 V, so the breaker is suitable for 690 V line-to-line systems with margin.
Auxiliary contacts and communication
The breaker ships with one auxiliary switch plus one trip alarm switch (HP type) pre-installed. The ETU850 has a communication function onboard.
Physical fit and panel integration
Dimensions are 181 mm height, 105 mm width, 86 mm depth.