By Eileen Harvey
Reliable cabling is the backbone of safe and efficient operations. From powering heavy-duty motors and running complex automation systems to ensuring stable communication between different pieces of equipment, the choice of cable type is crucial for optimal performance.
Among the myriads of industrial cable types available, variable frequency drive (VFD) cables and tray cables stand out as two of the most utilized options. Each type is engineered to fulfill specific functions, catering to the unique demands of various applications.
On the other hand, tray cables are versatile cables used primarily for power distribution and communication in cable tray systems, providing a reliable means for carrying electrical power and signals. Misusing one type for the other can result in serious consequences, including electrical interference, system malfunctions and, ultimately, costly downtime.
What Are VFD Cables?
VFD cables are specialized cables designed to connect variable frequency drives to motors. Since VFDs regulate motor speed using pulse-width modulation (PWM) signals, they generate electrical noise (EMI/RFI) that can disrupt nearby equipment if not properly managed.
VFD cables have several distinctive features. They have heavy-duty shielding to reduce electromagnetic interference (EMI) and are designed for flexibility, suitable for dynamic applications. They are resistant to oil, chemicals, UV and mechanical stress. And they’re rated for 0.6/1kV voltage classes to handle motor power safely.
Applications of VFD cables include: motor control in CNC machines, pumps and conveyors; automation and robotics systems; and industrial environments with high electrical noise.
Recommended VFD Cables from TKD Kabel:
What Are Tray Cables?
Tray cables are multi-purpose industrial cables designed for general power and control wiring. They are commonly routed through trays, conduits and ducts in plants.
Tray cables can carry power, control and signal circuits. They’re available with basic shielding or unshielded options and are cost-effective for general applications. Tray cables are often rated for flame resistance, moisture resistance and UV protection.
Popular applications of tray cables include control panels and cable trays, HVAC, lighting and utility wiring, and power and control circuits in plants. They are useful in high-frequency motor drive systems and when nearby equipment is sensitive to electrical noise. They are good in harsh environments with oil, UV or chemical exposure, and for precision-driven automation where reliability is critical. Other uses: in control circuits or lighting when EMI isn’t a concern; for budget-conscious installations; in non-critical, low-interference environments; and when running through cable trays or conduits for power distribution.
Risks of Using the Wrong Cable
Using tray cables in VFD applications causes excessive EMI that can lead to motor failure. It can also trigger false signals in automation systems and it results in shorter cable life due to heat and electrical stress. On the other hand, using VFD cables when they are not required increases project costs without adding any benefits.
Best Practices for Cable Selection
- Analyze your environment (harsh, outdoor, chemical exposure?).
- Check the EMI sensitivity of nearby devices.
- Follow NEC/UL/CSA guidelines for compliance.
- Consult manufacturer recommendations, such as TKD Kabel’s industrial cable catalog.
Expert Tips and Recommendations
- Use VFD-rated cables in all drive-to-motor connections, even if tray cables seem cheaper.
- For long cable runs, ensure proper grounding to minimize interference.
- When installing tray cables, always follow bend radius and tray fill guidelines.
- Keep VFD and signal cables separated to reduce crosstalk.
Interesting Facts
- Up to 80% of motor failures in VFD-driven systems are caused by improper cabling or grounding.
- VFD cables can reduce electromagnetic emissions by up to 90% compared to tray cables.
- Tray cables, while cheaper, are not designed for high-frequency harmonics, making them unsuitable for drivers.
Both VFD cables and tray cables play important roles in industrial applications, but they are not interchangeable. VFD cables are built for high-frequency drive systems, offering EMI suppression and durability, while tray cables are versatile, general-purpose solutions for control and power distribution. For long-term reliability, safety and compliance, always choose the right cable for the right job.
Explore the full range of TKD Kabel through L-com. We’ll fill your orders fast, with same-day shipping on all qualified, in stock, online orders received Monday through Friday before 5 p.m. EST. For TKD-related inquiries, connect with our U.S-based TKD expert Eileen Harvey at eharvey@infiniteelectronics.com.
