The Siemens 4EP3801-6DS00 is a 3-phase commutating choke for converter applications, rated 400V AC at 50Hz with a continuous current of 45A and an inductance of 0.5mH. It's built to EN 61558-2-20, the standard for chokes used in power electronics.
What the ratings mean for your drive line
The 4% relative inductive voltage drop (at rated current, voltage, and frequency) tells you how much the choke will sag under load — that 4% is a design target that keeps the DC bus ripple in check for a 6-pulse converter front end. The 45A AC rating is the thermal limit at 40°C ambient, thermal class B (130°C rise). Push it past 45A and the 58W copper loss plus 16.5W iron loss start cooking the winding; the IP00 open-frame means it needs forced air or a clean, ventilated cabinet — no washdown, no dust.
Where it fits in the panel
This is a panel-mount component — no DIN rail, no enclosure. Dimensions 0.178m wide × 0.153m tall × 0.12m deep. Screw terminals for the main circuit, so expect a screwdriver and a torque spec from the drawing. Mount it close to the converter's input to keep the commutation loop short; long leads add stray inductance that works against the choke's job.