of the other system components.  That’s why selecting an appropriate VFD cable is so important.  By mitigating the harmonics generated by VFDs during operation, the cable can improve overall drive system reliability and longevity.

Special attention should be paid to the cable’s insulation type, impedance and shielding/grounding system.  Cables employing a heavy wall of thermoset insulation are recommended because of their proven electrical benefits and improved stability.  Look for highly protective shielding systems and, in some situations, continuous armoring might also be recommended because of the low impedance path they provide for common-mode noise to return to the drive.

When VFD cables are installed in close proximity to low-level communications cables and other susceptible devices, shielded instrumentation cable should be used.  It is also prudent to limit the run of a VFD cable parallel to instrumentation cables to 10 ft. or less to reduce the likelihood of radiated noise issues.
   
Conclusion

Clearly, selecting the right VFD system – and the right cables – is paramount to a successful implementation of variable frequency drive technology.  Once accomplished, however, migrating to VFD is an effective investment that can pay off dramatically in terms of reducing energy usage and carbon emissions, and in saving costs and extending the service life of costly capital equipment.