Beginning with the end in mind is not only one of the 7 habits of highly effective people, it’s also a great philosophy to have when working with variable frequency drive (VFD) cable! If you have variable frequency drives at your facility you probably have heard of variable frequency drive cable. VFD cable has been shown to improve system performance by reducing electromagnetic interference (EMI), minimizing ground currents, controlling common mode current (which if left uncontrolled can damage motor bearings) and more. You may know a lot or a little about this specially designed cable that runs from your drive’s inverter to the motor. A lot of companies make VFD cable and a lot of salespeople from these companies will tell you that you should be running this cable. They may be right, but that is only half the story. The other half of the story is if you don’t properly terminate this cable, you lose most of the benefits it can provide.
Southwire’s Variable Frequency Drive (VFD) Cable Gland provides the means to properly terminate a VFD cable’s overall shield. The gland can be used on Southwire’s copper tape shield VFD cables and copper braid/aluminum foil shield VFD cables. Drive manufacturers stress the importance of proper shield termination to help prevent premature motor failure due to bearing fluting as well as operational issues associated with communication and control equipment located in close proximity to uncontrolled common mode currents. The VFD EMC Cable Gland provides a low impedance path at high frequency for common mode current created by the drive to the inverter via the shield and minimizes potential problems. Proper termination requires cable termination at both the drive and the motor end of the cable. Southwire’s VFD Cable Gland may be used on both copper tape and copper braid shields. Each gland includes a properly sized lock nut. Consult installation instructions for further details. Southwire offers VFD Cable Termination kits (SPEC 85451) as another cable termination option. See pdf for more details.