What this output reactor does in the drive line
The SIDAC 4EU4521-0CE00-0B is a 3-phase output reactor (output choke) rated for a maximum continuous current of 110 A and an inductance of 0.8 mH, designed to sit between a variable-frequency drive and the motor. Its primary job is to limit the rate of voltage rise (dV/dt) from the drive's PWM output and reduce capacitive coupling currents in long motor cables, protecting the motor winding insulation and extending cable life. The 4 kHz switching-frequency rating matches the typical carrier frequency of many industrial drives, so it filters the high-frequency content the drive injects into the line.
The 0.8 mH inductance is the value that determines the dV/dt slew-rate reduction; a lower inductance gives less filtering, a higher one more voltage drop. Thermal class H (180 °C insulation system) means the reactor can run hot without degrading the winding varnish — important in a sealed cabinet or near a drive that dumps heat into the enclosure. The IP00 rating means it's open-frame: no drip shield, no dust protection. Mount it inside a clean, dry panel or enclosure that provides its own IP rating.