The Siemens 4EU3052-3UB00-0AA0 is a three-phase mains choke (line reactor) designed to sit between the supply and a variable-frequency drive. It limits harmonic current, reduces voltage notching, and protects the drive's DC-link capacitors from line transients. Rated for 315 A maximum continuous current and 283.5 A at the rated operating point, it handles the full-load draw of a substantial motor — think a 200+ kW induction machine on a pump or conveyor. Winding is thermal class H (180 °C) per IEC 60085, so it survives the heat inside a crowded panel without derating prematurely.
This is an open-frame choke — IP00, no enclosure. It mounts inside a cabinet, typically on a mounting plate or chassis, not on a DIN rail. The main circuit connects via flat-type terminals (bus-bar style), not ring lugs or screw clamps. Plan for a footprint of 0.3 m wide by 0.269 m tall by 0.221 m deep, and allow clearance around it for airflow: the coil dissipates 216 W and the iron core another 129 W, so forced ventilation or a generously sized cabinet is needed to keep ambient below the 40 °C rating point.
The choke carries UL and CSA recognition per EN 61558-2-20, which covers the safety of chokes and reactors for industrial use. That means it is accepted in North American panels without a separate field-evaluation sticker. The thermal class H winding and the 50/60 Hz rating are standard for global installation.