What this MCCB carries — and what it means for a panel
The Siemens 3VA2325-6HN32-0DA0 is a SENTRON 3VA2 molded case circuit breaker (MCCB) rated for line protection, with a continuous current Iu of 250 A and a 3-pole configuration. The ETU350 electronic trip unit handles overcurrent protection, and an integrated undervoltage release (UVR) is fitted as standard — so if your control voltage drops, the breaker trips without a separate shunt-trip module. Breaking capacity is specified across several voltages: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 40 kA at 690 V. At 415 V, that 187 kA rating puts it in the high-interrupting category for industrial distribution — it will clear a bolted fault without upstream fuses needing to coordinate. Dimensions are 110 mm deep, 138 mm wide, and 248 mm tall. That 138 mm width is the standard 3-pole MCCB footprint for this frame size; it fits the same DIN-rail or panel-mount cutout as other 3VA2 250 A units, so a panel laid out for a 3VA2 frame will accept this breaker without re-drilling.
Thermal derating — what the 250 A rating actually delivers
The 250 A rating holds flat from 40 °C through 50 °C ambient. Above that it derates: 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 at 60 °C, plan for 235 A continuous — the breaker won't nuisance-trip, but you lose 15 A of headroom. Maximum power loss is 40 W at rated current. That's modest for a 250 A frame, but in a sealed, high-density panel the heat adds up — account for it in your thermal budget.