Three-phase line choke for drive harmonic mitigation
The Siemens 4EU2452-3GA00-0AA0 is a three-phase line choke rated for 350 A continuous current with 0.3 mH inductance per phase, built to EN 61558-2-20 for isolation and safety applications. It sits between the supply and a variable-frequency drive or inverter to smooth current ripple, limit harmonic distortion, and protect the DC bus from line transients.
The 350 A current rating (Ithmax 1) is the thermal continuous current the choke can carry without exceeding its temperature rise at 40 °C ambient (Ta/Isokl 40 /H). That is the number to match against your drive's input current, not the motor full-load amps — the choke sees line-side current, which includes harmonics and can be higher than the motor draw. The 0.3 mH inductance (LN) is the per-phase value that defines the impedance at the switching frequency; for a typical 6-pulse drive, this inductance reduces current THD by roughly 30–40 % compared to a choke-less installation.