Spacing of cable tray supports and hangers of various specifications

Cable tray hangers should be spaced according to cable type, tray material, load, and installation environment, typically ranging from 1.2 to 3 meters for standard runs, with closer spacing for heavy or sensitive cables.

General Guidelines

• Standard horizontal runs: For typical power and control cables, hangers are generally spaced every 1.2 to 1.5 meters for ladder or solid-bottom trays, depending on the cable weight and tray type .
• Heavy-duty or high-load trays: For trays carrying large bundles or heavy cables, spacing may need to be reduced to 1 meter or less to prevent sagging and mechanical strain .
• Vertical risers: Hangers or support rods should be installed at every 1.2 to 1.5 meters, ensuring stability and preventing lateral movement .
• Mesh or wire trays: Rung spacing is typically 150–230 mm (6–9 inches) to support instrumentation and control cables while maintaining proper airflow .
• Parallel tray installations: When two trays are installed side by side at the same height, maintain a minimum distance of 0.6 meters between them to allow access, ventilation, and maintenance .

Material and Environmental Considerations

• Steel or stainless steel trays: Standard spacing applies, but corrosion-resistant coatings may be required in humid or industrial environments .
• Aluminum trays: Lightweight trays may allow slightly longer hanger spacing, but mechanical load and cable weight must be considered .
• Fire-resistant installations: All supports must be made of fire-resistant materials to prevent premature failure during a fire, as required by BS 7671 .

Additional Recommendations

• Ensure hangers are rigid and properly anchored to the building structure to prevent sagging or vibration.
• Maintain adequate clearance for heat dissipation, inspection, and future cable additions.
• For instrumentation and control cables, closer hanger spacing may be necessary to prevent electromagnetic interference and maintain signal integrity .
• Always follow manufacturer-specific guidelines and local electrical codes, as spacing requirements can vary depending on cable type, tray design, and installation conditions . By adhering to these spacing guidelines, cable trays will maintain structural integrity, prevent mechanical strain on cables, and ensure safe, efficient operation over the system's lifetime.