What kind of cable is best for use in cable trays

Tray-rated cables, particularly Type TC (Tray Cable) and TC-ER (Exposed Run) cables, are the best choice for installation in cable trays due to their durability, code compliance, and versatility.

Why Tray Cables Are Ideal

Tray cables are specifically designed for installation in cable trays, raceways, or supported by messenger wires. Unlike standard electrical cables, they feature enhanced insulation and jacketing to withstand mechanical stress, moisture, sunlight, oil, and chemical exposure, making them suitable for harsh industrial and commercial environments . They are UL listed and tested for flammability, crush, and impact resistance, ensuring safety and reliability .

Common Types of Tray Cables

1. Type TC (Tray Cable)
   • Rated typically for 600V, with some versions up to 1000V or 2000V .
   • Used for power, control, lighting, and signal circuits in industrial and commercial settings .
   • Can be installed in cable trays, raceways, or direct burial if specifically rated .
   • Subtypes include VNTC (Vinyl Nylon Tray Cable) and XHHW (Cross-linked Polyethylene High Heat-resistant Water-resistant Tray Cable), with XHHW offering superior heat and moisture resistance .
2. TC-ER (Tray Cable with Exposed Run Rating)
   • Designed for short exposed runs (up to 6 feet) between the tray and equipment without conduit .
   • Includes impact- and crush-resistant jacketing, meeting additional UL standards .
3. ITC (Instrumentation Tray Cable)
   • Intended for low-voltage control, signal, and communication circuits (≤150V, ≤5A).
   • Often used for PLCs, DCS systems, and instrumentation in industrial plants .
4. PLTC (Power Limited Tray Cable)
   • Used for Class 2 and Class 3 power-limited circuits, such as alarm systems, intercoms, and building automation .
   • Typically rated at 300V and available in flame-retardant versions .

Key Considerations

• Voltage Rating: Choose cables rated for the system voltage (commonly 300V or 600V for industrial applications).
• Environmental Resistance: For outdoor or harsh environments, select XHHW or other thermoset-insulated cables for heat, moisture, and UV resistance .
• Code Compliance: Ensure cables are UL listed and marked as tray-rated, meeting NEC Section 392 requirements .
• Mechanical Protection: For areas prone to physical damage, use TC-ER or armored cables.
• Application Type: Power, control, signal, or instrumentation circuits may require different tray cable types (TC, ITC, PLTC).

Conclusion

For most industrial and commercial installations, Type TC tray cable is the standard choice due to its versatility, durability, and compliance with NEC and UL standards. For short exposed runs, TC-ER provides additional protection without the need for conduit. Specialized applications may require ITC or PLTC cables. Selecting the appropriate tray cable ensures safety, longevity, and reliable performance in cable tray systems .