The Siemens 4EU4521-0AN00 is a 3-phase AC commutating choke for converter applications, rated at 1560 A and 830 V. It's built for high-current DC-link or line-side commutation duties where you need to limit di/dt and smooth the current ripple — think large drives, rectifier bridges, or regenerative converter banks. The 0.019 mH inductance and 2% relative voltage drop tell you it's a low-impedance design, so it handles high surge currents without saturating the core too early.
Rated 1560 A continuous at 830 V AC — that's the thermal current limit at 40 °C ambient with class H insulation (180 °C hot-spot). The DC rating climbs to 1911.7 A, so if you're using it on the DC side of a 6-pulse or 12-pulse rectifier, you get extra headroom. The 700 W coil loss plus 404 W iron loss add up to about 1.1 kW of heat to vent; IP00 means no enclosure — mount it in a ventilated cabinet or a dedicated choke bay with clearance for airflow. Flat-type terminals on the main circuit. Width 0.46 m, height 0.435 m, depth 0.293 m.