What is the acceptable spacing between cable tray supports

The typical spacing between cable tray supports ranges from 1.5 to 3 meters for horizontal runs, with vertical supports preferably less than 2 meters apart, depending on tray type, load, and installation conditions.Horizontal Support SpacingFor straight horizontal sections, the support span between cable tray supports is generally 1.5 to 3 meters. This range ensures stability, prevents sagging, and allows for easy maintenance and cable access. At corners or bends, supports should be installed on each side symmetrically, with hanger spacing typically not exceeding 1.5 meters to avoid stress on the cables . Heavy-duty or long-span trays may allow supports up to 6 meters (20 feet), but this must be verified against the manufacturer's load capacity chart .Vertical Support SpacingFor vertical cable tray runs, supports should be fixed to the building structure at intervals preferably less than 2 meters. Long vertical runs exceeding 30 meters may require strain relief sections or short horizontal offsets to prevent excessive tension on the cables . This ensures the cables remain secure and reduces mechanical stress on terminations.Additional ConsiderationsHanging rod supports should have a minimum diameter of 8 mm for stability .Fixed supports are critical at tray beginnings, ends, corners, T-junctions, and spans over 30 meters to distribute weight and prevent sagging .Cable type and weight influence support spacing; stiffer cables like MDPE require greater spacing to maintain acceptable deflection, while flexible cables like LSOH may allow closer supports .Manufacturer instructions and NEC 392 standards should always be consulted, as they provide specific guidance for tray type, load, and environmental conditions .SummaryHorizontal runs: 1.5–3 meters (typical), up to 6 meters for heavy-duty traysVertical runs: