Cable trays for lighting wires

Yes, lighting wires can be run through cable trays if they are properly rated for tray use, such as Type TC (Tray Cable) or metal-armored (Type MC) cables, and installed according to NEC Article 392.

Cable Tray Basics

Cable trays are support systems for electrical cables, including power, signal, communication, and optical fiber cables. They are not raceways; they provide open support rather than fully enclosing wires, which allows for ventilation and easier maintenance . Common types include ladder trays, which allow air circulation and heat dissipation, and solid or ventilated troughs, which provide more continuous support for smaller or sensitive cables .

Permissible Cable Types

Not all cables can be placed in a tray. Because trays are exposed to air, the wires must have durable insulation. The NEC specifies that cables in trays should be Type TC (Tray Cable) or metal-armored (Type MC) . Standard non-tray-rated lighting wires may not be suitable unless they meet these requirements.

Separation and Safety Considerations

• Mixed voltages: High-power and low-power cables should not share the same tray unless a solid divider is used to prevent interference .
• Fill ratio: Avoid overcrowding; the tray should not exceed its recommended fill to prevent overheating .
• Dividers: Use built-in or added dividers to separate lighting wires from data or communication cables to reduce electrical noise .
• Covers: While not always required, covers can protect cables in high-traffic areas or outdoor installations .

Installation Tips

• Secure cables properly to prevent sagging or movement, especially in vertical trays .
• Maintain minimum bend radii when exiting the tray to avoid damaging insulation .
• Consider environmental factors such as moisture, heat, or corrosive conditions when selecting tray material and cable type . In summary, lighting wires can be run through cable trays if they are tray-rated or armored, properly separated from other cable types, and installed following NEC guidelines and manufacturer recommendations. This ensures safety, reduces interference, and allows for easier maintenance.