Rating and trip unit
The Siemens SENTRON 3VA2325-0HL32-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated for 250 A continuous current, flat from 40 °C through 70 °C — no derating needed across that band. The ETU320 electronic trip unit provides LI protection (long-time and instantaneous), with a maximum continuous current rating of 400 A for the frame, so the 250 A plug is the limiting element. Breaking capacity is 440 kA at 415 V AC and 187 kA at 690 V AC, which covers high-fault utility feeds and large motor branch circuits.
Dimensions are 248 mm high, 138 mm wide, 110 mm deep. Operating temperature range is -25 °C to 70 °C, storage from -40 °C to 80 °C. Power dissipation at full load is 37.5 W maximum — account for that in enclosure thermal calculations.