The Siemens SENTRON 3VA2225-5JQ32-0AB0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, carrying a continuous current of 250 A at 40 °C through 50 °C without derating. Above that, the thermal curve drops to 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C — so if this lives in a hot panel, size the load against the 70 °C figure, not the nameplate 250 A. Breaking capacity is voltage-dependent: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 4.5 kA at 690 V. That 121 kA at 415 V is the number to check against your transformer fault-current study — if your available fault is under that, this breaker clears it without cascading upstream. It includes a communication function for integration into a monitored distribution system, and comes with two HP auxiliary switches fitted. The design is line protection (not motor or generator protection), so it's the right choice for feeder and main breaker duty in a panelboard or switchboard.
Physical fit and panel integration
Dimensions are 181 mm high, 105 mm wide, 86 mm deep. The 105 mm width is the standard 3-pole MCCB footprint for this SENTRON frame size — it mounts on a DIN rail or bolts directly into a panel bus. Verify the bus-bar spacing against the 86 mm depth when routing behind the panel door. Maximum power loss is 48 W at rated current. That's moderate for a 250 A frame; account for it in the enclosure thermal calculation if the breaker is in a sealed cabinet with other heat sources.