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). This is a description of how to select, install, and support these metal or plastic frames, on which electrical wires are installed. You should consider it as a series of instructions that make the buildings resistant to. NEC Article 392 explains cable trays, their components, appropriate wiring methods for cable trays, and instances where they are and are not permitted for use. Here is the summary of the main points found in NEC Article. NEC Article 392 outlines the key rules for installing and maintaining industrial cable tray systems. 305(a)(3), or comparable standards promulgated by States operating OSHA-approved State plans.
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