A Vertical Cable Tray is a specialized support system designed to carry electrical and data cables securely in a vertical or riser direction. 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. Perforated cable trays are commonly used in: They are particularly effective when: A solid bottom cable tray features a fully enclosed bottom surface with continuous side rails, and no ventilation openings. Fill Rules for Multiconductor Cables 3. Each cable tray type performs a different function and comes in various materials such as aluminum, galvanized steel, and FRP.