How to build a support for side-by-side cable trays

Side-by-side cable trays can be securely supported using properly spaced hangers, cross members, and tray clips to ensure load distribution, alignment, and safe cable management.

Key Considerations

When installing side-by-side cable trays, the support system must account for:

• Load capacity: Each hanger should support the combined weight of the trays and cables, typically up to 318–340 kg per hanger .
• Support spacing: Maximum spacing between supports is generally 3.6 meters, but this may vary depending on tray type and load .
• Alignment: Trays must be level and parallel to prevent sagging and ensure proper cable routing .
• Material selection: Steel or stainless steel is commonly used, with galvanization or corrosion-resistant coatings for durability .

Support Methods

1. Trapeze or Swing Support
   • Install vertical hangers from the ceiling or structural beam.
   • Thread hex nuts 25–50 mm above the tray bottom and slide on square washers.
   • Attach a cross member between hangers, ensuring holes are slightly larger than the all-thread rod for adjustment.
   • Secure tray clips to the cross member, allowing horizontal adjustment for side-by-side trays .
2. Center-Hung Supports
   • Ideal for side-by-side trays, allowing cables to be deposited from each side.
   • Use a single cross member to support multiple trays, reducing the number of hangers and simplifying installation .
3. Wall or Bracket Supports
   • For trays mounted along walls, use wall brackets or cantilever arms to support each tray.
   • Ensure brackets are rated for the combined load of adjacent trays .

Installation Steps

1. Plan tray layout: Determine tray type (ladder, ventilated trough, or mesh), width, and spacing between trays.
2. Mark support locations: Based on maximum span and load, mark positions for hangers or brackets.
3. Install hangers or brackets: Secure vertical supports to the ceiling, wall, or structural beam.
4. Attach cross members: For side-by-side trays, use cross members to connect hangers and provide a level base.
5. Mount trays: Place trays on supports, using tray clips to secure them. Ensure trays are parallel and level.
6. Check alignment and load: Verify that trays are properly supported and can handle the expected cable weight.
7. Bonding and grounding: Ensure all trays are electrically bonded according to NEC or local codes .

Additional Tips

• Use ventilated trays for heat dissipation if power cables are installed.
• Maintain minimum bend radius for cables when trays change direction.
• For corrosive or high-moisture environments, consider FRP or coated trays .
• Always follow local electrical codes and manufacturer guidelines for safe installation . By following these steps and using appropriate support elements, side-by-side cable trays can be installed safely, efficiently, and in compliance with industry standards.