The Siemens 4EP4001-8DS00 is a commutating choke (line reactor) designed for converter input circuits. It sits between the AC supply and the converter's rectifier, smoothing current ripple and limiting di/dt during commutation. This specific unit is a 3-phase, 400V AC, 50Hz choke rated for 63.9A continuous (71A maximum), with an inductance of 0.4mH and a relative inductive voltage drop of 4% at rated conditions.
The 63.9A rated current (71A max) means this choke can handle the continuous input current of a converter drive sized around that amperage at 400V AC. The 4% inductive voltage drop is the key parameter: it tells you the choke will drop about 16V at rated current (4% of 400V), which is typical for commutating chokes and must be factored into the drive's input voltage budget. The 0.4mH inductance provides enough impedance to limit current rise during thyristor or IGBT commutation, reducing harmonic distortion and protecting the converter's semiconductors. Thermal class B insulation (130°C hot-spot) per IEC 60085 means the choke is rated for a 40°C ambient with a 75W coil loss and 32.1W iron-core loss. The IP00 protection rating means it's an open-frame component — no enclosure, no drip protection. The flat-type terminals accept busbar or crimp lugs, typical for higher-current power connections.
Mounting dimensions: 0.219m wide, 0.179m tall, 0.143m deep. The IP00 open-frame design means it needs to be bolted inside a cabinet on a mounting plate — no DIN-rail clip. The flat-type terminals are sized for the 63.9A rating; plan for busbar or cable lugs with appropriate cross-section. The 75W coil loss plus 32.1W iron loss totals about 107W of heat to dissipate inside the enclosure, so factor that into your cabinet thermal calculation.