Generally, standard trays require supports every 6 to 10 feet, while heavy-duty, long-span trays can handle distances of up to 20 feet between supports. To determine the proper spacing, consult the manufacturer's load capacity chart, which accounts for the total weight of the. NEC Article 392 outlines the key rules for installing and maintaining industrial cable tray systems. These systems, made from metal or plastic, are open structures designed to support electrical conductors, ensuring proper organization and safety. For non-galvanized cable trays, both ends of each connection plate shall be bridged with a copper jumper. In this case, you can skip the jumpers as long as the metal stays tightly bolted. It also focuses on construction and installation practices for cable trays. Following NEC guidelines ensures that cable trays are safely integrated into the broader electrical network, meeting regulatory safety standards and. NEC Article 392 defines cable tray as "a unit or assembly of units or sections and associated fittings forming a structural system used to securely fasten or support cables and raceways.
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