What this MCCB delivers — and what it doesn't
The Siemens SENTRON 3VA2325-7MN32-0CA0 is a 3-pole molded case circuit breaker rated for a continuous current of 250 A, built for motor protection duty. The ETU350M electronic trip unit handles phase-failure detection and undervoltage release is integrated.
Current derating and thermal reality
The 250 A rating holds flat from 40 °C to 50 °C. Above that, derate linearly: 240 A at 55 °C, 235 A at 60 °C, 230 A at 65 °C, 225 A at 70 °C. If your panel ambient runs above 50 °C, size the feeder and bus accordingly. Maximum power loss is 40 W — that's the heat to vent. The enclosure depth of 110 mm, width 138 mm, and height 248 mm fit standard SENTRON 3VA panel cutouts; verify gland-plate clearance for the incoming cables. Operating range is -25 °C to 70 °C; storage from -40 °C to 80 °C.