Due to their exposure to the open air because of the cable trays, the wires contained within need a very durable outer covering. The regulations dictate that the cables must either be Type TC (also known as Tray Rated) or must be metal-armored (Type MC). The short answer is no. Cable tray systems provide a safe, organized, and flexible method for supporting insulated conductors and cables in commercial and industrial electrical installations. These systems are used in a wide range of applications, from office buildings and hospitals to manufacturing. Cable trays are vital in electrical installations, providing secure pathways for power, communication, and control cables across residential, commercial, and industrial settings. NEC Article 392 governs cable tray installations, covering tray types, fill. Use NEC 392 for tray rules, but still size conductors from NEC 310. For long industrial feeders, check voltage drop after ampacity; 3% branch and 5% total remain practical.
[PDF Version]