The 3VA2225-0KP42-0AA0: Breaking capacity is 440 kA at 415 V AC and 187 kA at 690 V AC — that's enough to handle high-fault utility feeds or transformer secondaries without cascading upstream breakers. The ETU850 trip unit includes a communication function and other measurement functions, meaning it can talk to a BMS or PLC for power monitoring and trip event logging — not just a dumb thermal-magnetic breaker.
Thermal derating — the real-world current rating
This breaker holds its full 250 A rating from 40 °C up through 50 °C ambient. At 55 °C it derates to 238 A, at 60 °C to 225 A, and at 70 °C to 200 A. If you're stuffing this into a hot panel next to drives or transformers, use the 55 °C or 60 °C column for your load calculation — not the nameplate 250 A. Maximum power loss is 48 W, so plan for that heat inside the enclosure. That's a standard SENTRON 4-pole frame size — it'll drop into existing 3VA panel cutouts and busbar arrangements without re-drilling.
N-conductor protection and adjustments
Neutral protection adjustable: OFF or 20 % to 100 % of phase current. There's no undervoltage release and no ground-fault monitoring built in — those are add-on accessories if you need them. The trip indicator is also absent on this variant, so you'll need a remote indication accessory or rely on the communication function for trip status.