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.
[pdf] This fabrication and welding procedure governs the welding of components to the requirements of AWS D1. 1 (Reference 1) and Mechanical and Metal Trades Handbook 3rd Edition (Reference 2). Understand key welding methods, materials, design and quality-control for electrical enclosures — from TIG/MIG to distortion control and standards compliance. Ensure cleaning of each weld edge. 4 KV Substation of the ratings indicated above. These Distribution Cabinets are to be outdoor type nd to be fabricated out of 2 mm GI sheet steel. The body of the boxes shall have sufficient re- enforcement with suitable size of channels keeping a provision for fixin andle conforming to general. low-alloy constructional steels.
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