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). Selecting the correct cable tray for low voltage system—such as data networking, telecommunications, security, and building automation—is a critical decision that impacts system performance, scalability, and long-term reliability. A poor choice can lead to signal interference, difficult. NEC Article 392 outlines the key rules for installing and maintaining industrial cable tray systems. The last two items can also be accomplished with a solid fixed barrier. This is a description of how to select, install, and support these metal or plastic frames, on which electrical wires are installed.
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