The Siemens SENTRON 3VA2225-7KP32-0AB0 is a 3-pole molded case circuit breaker (MCCB) rated for a continuous current of 250 A, fitted with an ETU850 electronic trip unit. This is the line protection version — meaning it's configured for cable and busbar protection rather than motor protection, so no phase-failure detection or undervoltage release is built in. The interrupting ratings are substantial: 330 kA at 240 V, 242 kA at 415 V and 440 V, 187 kA at 500 V, and 6.3 kA at 690 V. That 330 kA at 240 V tells you this breaker is designed for high-fault-current installations — typically large distribution switchboards or transformer secondaries where available fault current is in the hundreds of kiloamps. The ETU850 release gives you communication capability and an additional measurement function, so it can report load current and event data back to a BMS or SCADA system.
Thermal derating and panel fit
The 250 A rating holds fully up to 50 °C ambient. Above that, it derates: 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C. If your panel ambient runs at 60 °C, you're limited to 225 A continuous — a critical number for coordination studies. The breaker measures 105 mm wide, 181 mm high, and 86 mm deep. That 105 mm width is standard for a 250 A frame in the SENTRON 3VA platform, so it fits the same panel cutout and busbar spacing as other 3VA2-frame breakers. Front protection is IP40, which is typical for enclosed switchgear — it keeps tools and fingers out but isn't rated for washdown. Maximum power dissipation is 48 W at rated current; factor that into your enclosure thermal calculation.