The Siemens SENTRON 3VA2225-7HL32-0CA0 is a 3-pole molded case circuit breaker (MCCB) rated for 250 A continuous current, with a massive 330 kA interrupting capacity at 240 V — that figure drops to 242 kA at 415/440 V, 187 kA at 500 V, and 6.3 kA at 690 V, so this breaker is sized for high-fault utility or transformer-fed main feeders where the available fault current is in the hundreds of kiloamps.
The 250 A rating holds flat from 40 °C to 50 °C ambient; above that it derates linearly to 241 A at 55 °C, 232 A at 60 °C, 222 A at 65 °C, and 213 A at 70 °C. If your panel ambient runs above 50 °C, the breaker still carries 213 A at 70 °C — no need to oversize the frame for a hot enclosure, but the power loss at full load is 50.5 W, so account for that heat in the enclosure thermal budget.