Siemens SENTRON 3VA2225-5KP32-0CA0 — 250 A MCCB with UVR and Communication
Its interrupting capacity reaches 187 kA at 240 V and 121 kA at 415 V, which means it can safely clear high-fault currents on the secondary side of a typical 400 V transformer without cascading upstream.
The 3VA2225-5KP32-0CA0 holds its full 250 A rating from 40 °C through 50 °C, then derates to 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C. Breaking capacity drops with system voltage: 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. At 690 V the breaker is still rated for line protection but the fault-clearing margin narrows — selectivity coordination studies should confirm the downstream devices stay within the 4.5 kA limit.
The 86 mm depth means it clears a typical 200 mm deep enclosure without forcing a deeper gland plate. Maximum power loss is 50.5 W, which should be factored into the enclosure thermal budget.