What this mains choke does on the line side
The Siemens 4EU4351-6UA00-0A is a three-phase mains choke (Netzdrossel für Frequenzumrichter) rated for 690 V AC at 50 Hz, with a maximum continuous current of 710 A and a rated current of 639 A. It sits between the supply and a variable-frequency drive to smooth line-side harmonics, limit inrush current, and protect the drive's DC bus from voltage notches. The 71 µH inductance and 4 % relative inductive voltage drop are sized for a drive of this current class — the choke absorbs enough reactance to keep the drive's input rectifier from drawing peak currents that would trip upstream breakers or distort the plant supply.
Mounting and thermal reality — IP00, flat terminals, Class H insulation
The flat-type terminals accept busbar or large cable lugs; expect to land the main circuit with bolted connections, not spring cages. At 706 W copper loss plus 243 W iron loss, the total heat dissipation is close to 950 W — that needs forced ventilation or generous cabinet volume. Thermal class H (180 °C) gives headroom for the core and windings under full load at 40 °C ambient. Dimensions are 0.46 m wide by 0.435 m tall by 0.265 m deep (–) — it's a substantial block that needs a dedicated mounting footprint, not a DIN-rail clip.
The choke is UL and CSA recognized, and designed to EN 61558-2-20. That covers the safety and performance requirements for chokes used in power electronics. No RoHS or REACH statement is in the evidence, but Siemens typically provides those on request for mature catalog parts.