What it is and what it does
The Siemens 4EP3701-7DS00 is a three-phase commutating choke designed for converter applications — it sits on the AC line side of a variable-speed drive or rectifier to limit current rise and reduce harmonic distortion. Rated for 400 V AC at 50 Hz, it carries a continuous AC current of 31.5 A (with a peak rating of 39 A) and provides 0.7 mH inductance per phase. The 4% relative inductive voltage drop at rated current tells you the impedance it adds to the circuit — enough to smooth commutation notches without dropping excessive voltage across the choke under load.
Key ratings — what they mean for fit
AC maximum current 31.5 A, AC rated current 28.35 A. DC rated current 38.6 A. Coil loss 55 W, iron-core loss 9 W. Ambient temperature rating 40 °C. Thermal class B.
Where it goes in the panel
This is a panel-mount component — no DIN rail, no enclosure, just an open-frame choke with screw terminals. The 0.178 m width, 0.153 m height, and 0.105 m depth mean it needs a flat mounting surface and clearance around the terminals for the screw-type connections (accepts up to the wire gauge that fits the terminal). IP00 means no protection against dust or moisture, so it must live inside a clean, dry cabinet or a ventilated enclosure. The three-phase connection is straightforward: line in, choke out to the converter, with the screw terminals taking the power wiring.