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). us-trations without notice. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned. A cable tray is a metal or non-metal structure used to lay electrical cables and wires, serving to support, protect, and guide the cables. What is the role of a cable tray in electrical engineering? A cable tray allows for the neat and aesthetic arrangement of cables, improves the reliability. In this installment of our Code Corner series, Ryan Mayfield focuses on the 2023 National Electrical Code (NEC) changes concerning cable trays, particularly section 690. Historically, the NEC has allowed cable trays, but has lacked specific guidelines for sizing conductors and using smaller. According to the NEC (National Electric Code), tray cable is defined as “a factory assembly of two or more insulated conductors, with or without associated bare or covered grounding conductors under a nonmetallic sheath, for installation in cable trays, in raceways, or where supported by a. Cable tray is the preferred wiring method for industrial facilities, data centers, and large commercial buildings where routing dozens or hundreds of cables through individual conduits would be impractical and expensive. NEC Article 392 governs cable tray installations, covering tray types, fill. Table 392. This table includes almost all common types of wire and cable found in the NEC.