TM Motor Chockes are used in drive motors with frequency converters. They are connected to the frequency converter's output if the cables between the converter and the regulated motor are long. They suppress adverse effects of capacitance represented by long cables.The capacitive component of the cable impedance, with respect to the power transistors switching frequency of the converter, may cause overload on the converter output, failing to supply the nominal current to the load. In addition to suppression of these effects, at the same time it will reduce the radiation of EMI voltage both: on converter output and on supply network direction. Insertion of motor chokes prescribes to the manufacturer of converters for motor cable lengths greater than 20-50 m depending on the type converter. Motor chokes are designed so that their voltage drop is not higher than 2% of output nominal voltage with the frequency 50Hz and with output voltage of converter 3x400V/230 V. For standard realization the limit modulation frequency of the converter is 3kHz. In case of requirement the higher modulation frequencies, please contact the manufacturer.  See details  pdf