That's useful for panels where you need to catch a ground leak without a separate relay.
That's a real advantage if your enclosure runs hot. The 140 mm width is the standard 4-pole MCCB footprint — it'll drop into most SENTRON 3VA panel bases without re-drilling.
Front face carries IP40 protection — fine for a dry indoor panel, but keep it out of washdown zones. No undervoltage release, no communication module, and no voltage-trip function on this variant; those are options on other 3VA order codes. If you need remote trip or status feedback, you'll add an auxiliary switch or shunt trip separately. The ETU330 is self-powered from the line current, so no control power needed for basic overcurrent protection.
