The Siemens SENTRON 3VA2225-6HN32-0BH0 is a 3-pole molded case circuit breaker rated for 250 A continuous current at 40 °C, with an ETU350 electronic trip unit configured for line protection. Its interrupting capacity reaches 242 kA at 240 V and 187 kA at 415 V, dropping to 6 kA at 690 V — the high 240 V figure means it handles heavy fault current on the secondary side of a step-down transformer or a low-voltage distribution bus without cascading upstream.
The 250 A rating holds flat from 40 °C to 50 °C, then derates linearly to 213 A at 70 °C. Mechanical endurance is 20,000 cycles, which is typical for a distribution-grade MCCB; not intended for frequent switching duty (that is a contactor's job). Maximum power loss is 50.5 W, so heat dissipation inside the enclosure needs to be accounted for in the thermal budget.