What this output reactor does on a VFD line
The Siemens SIDAC 4EU3652-0AR00-4BA0 is a 3-phase output reactor rated for 115 A maximum continuous current and a 3 kHz switching frequency, with an inductance of 0.35 mH. It sits between the variable-frequency drive and the motor to limit the rate of voltage rise (dV/dt) from the drive's PWM output, protecting motor winding insulation from reflected-wave damage on longer cable runs. The 400 V AC voltage class matches standard 400 V three-phase industrial mains. Rated for a 40 °C ambient with Class H insulation (thermal class 180 °C per IEC 60085), this reactor handles the thermal stress of continuous PWM duty without derating under normal conditions.
Sizing and fit considerations
At 0.35 mH and 115 A, this reactor is sized for medium-horsepower drives — typically 30–50 kW motors depending on cable length and drive switching frequency. The 3 kHz switching frequency rating matches the carrier frequency of many general-purpose VFDs; verify that your drive's PWM frequency does not exceed this value to avoid core saturation and overheating. Physical dimensions are 0.35 m wide by 0.32 m tall by 0.22 m deep. The flat-type terminals accept busbar or large-gauge cable lugs; plan for adequate bending radius and clearance around the connection points inside the panel.