The NEC requires that cable trays must be supported by members at an interval specified by the cable tray manufacturer, but not more than 5 feet for horizontal runs to support the weight of the cables and other loads. The NEC has a requirement for ladder-type cable trays. The National Electrical Code is a set of principles designed to promote public safety and welfare, as well as safeguard public health by regulating the design and operation of electrical facilities and. Let's dive deeper into the specific cable tray spacing requirements that you need to consider during installation to ensure both functionality and safety. Ensures space for maintenance, inspection, and airflow for heat dissipation; reduces risk of cable contact/short circuits. Clause 522-08-04 Where conductors or cables are not supported. 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.
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