The Siemens SENTRON 3VA1225-4EF42-0JH0 is a 4-pole molded case circuit breaker rated for line protection, with a continuous current of 250 A up to 50 °C and a short-circuit breaking capacity of 121 kA at 240 V — that's the figure that governs SCCR compliance in a 240 V panel. At 415 V it still holds 75.6 kA, dropping to 11.9 kA at 690 V.
Thermal derating and auxiliary fit
Rated 250 A at 40 °C, 45 °C, and 50 °C — no derating needed in a standard 50 °C enclosure. Above that it steps down: 243 A at 55 °C, 237 A at 60 °C, 230 A at 65 °C, and 223 A at 70 °C. The 57 W maximum power loss matters for heat rise in a tightly packed panel; check your enclosure's dissipation budget if you're grouping several breakers.