The Siemens 4EP4003-1DS00 is a three-phase commutating choke (line reactor) designed for converter front-end duty — it sits between the AC line and the rectifier to limit current rise, reduce harmonics, and protect the DC link from line-side transients. Rated for 500 V AC at 50 Hz, it carries a continuous current of 50.4 A (56 A maximum, 71 A peak), with an inductance of 0.00052 H and a relative inductive voltage drop of 4% at rated conditions. The 4% voltage drop is the key specification for sizing — it determines the impedance the choke presents to the drive's switching frequency. For a 500 V system, that drop is about 20 V line-to-line at full rated current, which the drive's DC bus regulation typically absorbs without issue.
The 50.4 A rated current (56 A maximum) is the thermal continuous rating at 40 °C ambient with Class B insulation (130 °C hot-spot limit per IEC 60085). The 71 A peak rating covers short-duration overloads — typical for a drive's inrush or a momentary load step — but sustained operation above 56 A will exceed the thermal design. Total power loss splits between the coil (80 W) and the iron core (25 W), for a combined 105 W at full load. That heat must be dissipated into the surrounding air; the IP00 enclosure means no fan or forced cooling is built in, so panel ventilation or derating is required if ambient exceeds 40 °C.
This choke mounts in the AC line path ahead of a variable-frequency drive or DC drive converter, typically on a mounting plate inside a control panel. Dimensions are 0.219 m wide by 0.179 m tall by 0.143 m deep — about the footprint of a large contactor.