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 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. You should consider it as a series of instructions that make the buildings resistant to. Cable trays can be installed indoors or outdoors, provided the tray materials suit the atmospheric conditions. 3 meters from the ceiling or any other obstructions.
