Selecting the right Variable Frequency Drive (VFD) cable is one of the most important steps in ensuring reliable performance and long-term protection of your motor and drive system. The proper cable minimizes voltage spikes, bearing currents, and electrical interference, helping maintain electromagnetic compatibility (EMC) and overall system stability.
Below are the key factors to consider when specifying or selecting a VFD cable.
Proper shielding helps contain electromagnetic interference (EMI) and radio frequency interference (RFI) generated by the drive.
Braid Shield: Provides good coverage and mechanical strength—suitable for most industrial environments.
Foil Shield: Offers 100% coverage and excellent high-frequency noise suppression.
Combination Shield (Braid + Foil): Delivers the best overall protection, ideal for long cable runs or high-noise areas.
Symmetrical Ground Design: Cables with three insulated ground conductors or a copper tape shield ensure balanced return paths and minimal common-mode noise.
Use twisted conductors to reduce magnetic field coupling and minimize radiated noise.
Select the correct gauge (AWG) to handle full-load current with minimal voltage drop.
Consider fine-stranded conductors for flexible installations involving tight bends or moving machinery.
Choose insulation rated for high voltage spikes (up to 2,000 V or more).
XLPE (Cross-Linked Polyethylene) or EPR (Ethylene Propylene Rubber) offer excellent thermal stability and dielectric strength.
Ensure the jacket is environmentally rated — oil-resistant, UV-resistant, or approved for tray or conduit use.
Use cables with dedicated ground conductors or integral copper tape shields for consistent high-frequency grounding.
Avoid using a single external ground wire, which can cause uneven impedance and worsen EMI problems.
Long runs (over 50–100 ft) can cause reflected wave voltage spikes, especially in systems with fast-switching IGBTs.
Choose low-capacitance VFD cables for long distances, and consider output filters or reactors to reduce reflection and electrical stress.
Confirm cable ratings for:
Temperature range (typically –40°C to +90°C)
Resistance to oil, moisture, and chemicals
Suitability for flexible tray or continuous motion use (e.g., TC-ER, MTW, or flexible cable types)
Compliance with minimum bending radius to prevent insulation cracking
Choose cables that meet or exceed:
UL/CSA listings (UL 1277, UL 2277, UL 1063)
IEEE 519 for harmonic control
NEC Article 336 (Type TC or TC-ER for tray installations)
EMC standards if operating near sensitive instrumentation
When choosing a VFD cable, prioritize:
✅ Effective shielding
✅ Proper grounding
✅ High insulation ratings
✅ Compliance with standards
A well-engineered cable ensures safe, efficient, and noise-free operation of your VFD system — protecting your investment and minimizing costly downtime.
Watch: VFD Cable Selector Tool Overview
Take the guesswork out of cable selection with the Belden VFD Cable Selector Tool.
It guides you step-by-step through voltage, current, length, and environment factors to find the perfect match for your application.
🎥 Watch: VFD Cable Selector Tool Overview
➡️ Try the Belden VFD Cable Selector Tool