Clearances: Maintain at least 12 inches of vertical clearance above trays for installation and maintenance access (2026 NEC update). Grounding: Metallic trays can serve as equipment grounding. 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. This is a description of how to select, install, and support these metal or plastic frames, on which electrical wires are installed. It also helps reduce the risk of. Some cable tray systems are appropriate for under floor use, despite the fact that they are normally suspended from ceilings (or) attached to walls. Tray Type and Material Selection Indoor: Painted steel or galvanized trays.
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