3 Reasons Why the Right VFD Cable is Important
VFDs are critical in today’s environment to ensure an efficient manufacturing process. They are used to control the frequency and voltage of an AC motor and yield additional performance and energy savings. Many operations professionals depend on them to regulate nearly every motor in a facility – sometimes hundreds of motors!
VFD cable is specifically engineered to carry power from the drive system to the motor and has been proven to extend motor life, improve efficiency, and avoid costly downtime.
Although VFD cable has become more popular over the last few years, many people have not yet realized the full benefits. Many facilities using VFDs expect a motor to fail every two years as a result of bearing or insulation failure. It’s important to note that this can be easily avoided and is often the result of the wrong cable placing excessive stress on the motor.
With that being said – why should you use VFD cable in your facility? We’ll share three reasons regarding the long-term benefits of using VFD cables and why it’s a safer, more reliable choice, and ultimately more cost effective.
1) The Right VFD Cable Can Prevent Premature Motor Failure
VFD systems are subject to harsh operating environments characterized by high voltage spikes and high levels of radiated noise.
How will using the wrong cable affect your motors? VFD outputs can cause a non-VFD cable to broadcast noise that can affect nearby devices. Commonly used alternative products such as unshielded tray cables or THHN wire are not suited for this application and can cause your motors to fail prematurely. These failures can cause downtime, productivity loss, and the need for new equipment, which is often very expensive.
2) The Right VFD Cable Is a Safer Choice
Along with equipment faults, using a non-VFD cable can be a safety hazard for workers, putting them at risk of electrical shock.
Proper insulation and robust shielding are critical in preventing unwanted interaction between systems (and humans). When selecting VFD cable, you should look for XLP insulation because it can withstand voltage and heat significantly better than THHN and generic control or tray cable.
3) The Right VFD Cable Ultimately Reduces Costs
When considering costs, the initial investment in VFD cable can be more expensive than an initial investment in a non-VFD cable. However, the upfront investment can provide greater savings in the long run.
When considering the potential risks of a multi-million dollar downtime event, the incremental cost of the appropriate VFD cabling infrastructure is minimal. Proactively installing high-performance VFD cable can prevent these incredibly costly incidents.
Based on case studies, the proper VFD cable and installation may increase motor life by 250 percent! They significantly reduce stress on the motor, increasing the mean time between failures to five years or more. Making smart selections from the beginning can reduce expensive maintenance and replacement costs.
How a Distributor Can Help
Now that we have covered why the right VFD cable is important, let’s discuss the how.
More often than not, many operators don’t know to request VFD cable, and contractors tend to gravitate toward the cheaper option by default. To make matters more complex, there are no standards for VFD cable, so any construction-grade cable can be labeled a “VFD cable,” even if it only marginally improves reliability. You must select the right high-performance VFD cable to maximize the benefits of using a complete VFD system.
Navigating the VFD cable landscape can be complex, but the right distributor has the experience and product knowledge to guide your decision.
Below is a quick guide to differentiate between two to get you started.
Construction-Grade VFD Cable
High-Performance VFD Cable
Copper-tape shielded building wire
Braided shield with DuoFoil™ construction or dual copper tapes
VFD Grade XLPE insulation
1 ground conductor often in 3 segments meeting NEC minimums
Insulated grounds, shield and drains equivalent to 3 or more conductors at ground potential
Bare copper, Class B stranding, Low flex
Tinned copper conductors High strand count High Flex
Not recommended by the manufacturer of your VFDs
Recommended for use by your VFD manufacturer NFPA 79 Rated