The Siemens SIDAC 4EU3951-0AS00-0A is a 3-phase output reactor rated for 200 A maximum continuous current with 0.2 mH inductance per phase, designed to sit between a variable-frequency drive and the motor cable. The 0.2 mH inductance limits the rate of current rise from the drive's PWM output, reducing voltage spikes that stress motor winding insulation — especially on long cable runs or with older motors. Rated switching frequency of 3.2 kHz matches the typical carrier frequency of many general-purpose drives.
Open-frame IP00 construction — no enclosure, so it mounts inside a cabinet on a backplate or mounting rail. Dimensions are 0.41 m wide by 0.38 m tall by 0.22 m deep, which is a substantial footprint; plan for adequate clearance around the flat-type terminals (0.2–2.5 mm² stranded or solid) for wrench access. Class H insulation (180 °C) means the reactor can run hot without degrading the winding varnish, which is typical for reactors in continuous-duty VFD applications. Ambient temperature rated at 40 °C; derate current if cabinet ambient exceeds that.