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. The National Electrical Manufacturers Association (NEMA) also publishes three consensus standards that apply to the proper manufacture and installation of cable trays: ANSI/NEMA-VE 1-1998, Metal Cable Tray Systems; NEMA-VE 2-1996, Metal Cable Tray Installation Guidelines; and NEMA-FG-1998. NEC Article 392 outlines the key rules for installing and maintaining industrial cable tray systems. Here is the summary of the main points found in NEC Article. Question 1: Can mechanical utility piping or tubing containing water or compressed air be installed in cable trays with electrical cables? Answer: No.
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