This is the line-protection variant — meaning it's sized and coordinated for feeder circuits, not motor-starting duty.
The interrupting rating drops predictably as voltage rises: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 17 kA at 690 V. For a 400 V panel, 121 kA covers most utility-fault scenarios without cascading upstream.
At 50 °C it derates to 570 A; at 60 °C to 510 A; at 70 °C to 450 A. Mounting in a sealed, non-ventilated enclosure pushes internal ambient up — check the actual cabinet temperature against this curve before locking in the BOM line. Physical footprint is 138 mm wide × 248 mm high × 110 mm deep, which fits standard SENTRON mounting patterns; no panel rework needed if replacing an existing 3VA2 frame.
Trip unit and auxiliary complement
The ETU550 electronic trip unit provides adjustable long-time, short-time, instantaneous, and ground-fault protection curves — it's the mid-tier electronic release in the 3VA family, offering more selectivity than a thermal-magnetic but without the full communications suite of the ETU600. That's enough for remote status and trip indication without adding a separate module.