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). cal devices or other equipment. Channel tray can protect against electromagnetic inte, is a welded wire-mesh cable management system made of high-strength steel wire. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned in this technical guide only apply to our own cable management ranges and cannot under any circumstances be transposed to si osure, overheating or. Cable trays create a clear pathway for wires. What Is a Galvanized Cable Tray? A galvanized cable tray is made from steel. The primary rulebook used in the safe use of cable trays is NEC Article 392. This is a description of how to select, install, and support these metal or plastic frames, on which electrical wires are installed.