SENTRON 3VA2 motor-protection MCCB with ETU350M — 250 A frame, 330 kA IC
The Siemens 3VA2325-7MN32-0DA0 is a 3-pole SENTRON molded case circuit breaker in the motor protection version, rated 250 A at 40 °C and carrying a 330 kA interrupting capacity at 240 V. That breaking figure at 240 V is the highest in the 3VA2 line — it handles fault currents up to 330 kA without cascading upstream, which means it can sit at the main incomer in a high-fault panel and still clear a bolted fault before the transformer secondary breaker sees it. The ETU350M electronic trip unit gives you adjustable overload and short-circuit protection curves, plus phase-failure detection built in. At 400 V AC-3 duty it switches motor loads rated up to 110 kW, so it's sized for a medium motor centre feeding pumps, conveyors, or compressors. The unit ships with an undervoltage release (UVR) fitted — that's the -0DA0 suffix. If your control voltage drops below the dropout threshold, the breaker trips immediately, which is standard practice for safety circuits that need to kill power on loss of control supply. No auxiliary contacts or ground-fault module are included on this variant; those would need to be added externally if your BOM calls for remote status or earth-leakage protection.
Thermal derating and panel fit
Rated current holds flat at 250 A from 40 °C up to 50 °C (–). Above that it derates linearly: 240 A at 55 °C, 235 A at 60 °C, 230 A at 65 °C, and 225 A at 70 °C (–). If your panel ambient runs 55 °C or higher, factor that 4–10 % reduction into the load schedule. The 40 W maximum power loss is dissipated through the case — allow clearance around the sides for natural convection, especially when ganged with other breakers in a switchboard section. Front IP40 means the face is protected against tools and wires ≥1 mm, but the terminals are not sealed; mount it in a clean, dry enclosure or a dedicated MCC bucket. Dimensions are 248 mm high × 138 mm wide × 110 mm deep. That 138 mm width is the standard 3-pole 3VA2 frame footprint — it fits the same mounting cut-out and bus-bar spacing as other 3VA2 breakers in the 250 A class. The 110 mm depth leaves room behind the panel door for the rotary handle mechanism and wiring gutters.