Cable tray support crossarm installation

Crossarm supports provide stable, long-term support for large cable trays, ensuring proper load distribution and safe cable management.

Overview of Crossarm Support Systems

Crossarm supports are used primarily for large-sized cable trays to provide robust horizontal support when trays are suspended from ceilings. They are designed to maintain stability, facilitate maintenance, and handle heavier cable loads compared to smaller hoisting frames used for light trays . The system typically includes:

• Crossarm: Horizontal bar supporting the tray.
• Suspension rods (lead screws): Vertical connectors linking the ceiling to the crossarm.
• Five-piece fastening kit: Bolts, nuts, washers, and other accessories to secure the assembly.
• Cable tray sections: Mounted on top of the crossarm for cable routing.

Installation Steps

1. Determine Support Spacing:
   • Recommended spacing is 1.5 to 2 meters between crossarms for large trays .
   • Ensure spacing accounts for the tray's weight and the total cable load.
2. Install Suspension Rods:
   • Attach rods to the ceiling using expansion anchors or other approved mounting hardware.
   • Rods should be vertical and aligned with the crossarm positions.
3. Mount Crossarms:
   • Connect the crossarm to the suspension rods using the five-piece fastening kit.
   • Ensure the crossarm is level and securely fastened to withstand tensile forces and vibrations.
4. Attach Cable Trays:
   • Place the cable tray sections on the crossarm.
   • Secure trays using bolts or clamps to prevent movement.
   • Maintain proper tray alignment and continuity across multiple crossarms.
5. Grounding and Safety:
   • Install grounding conductors and washers to prevent static, EMI, or electric shock.
   • Ensure all metallic components are corrosion-resistant and properly bonded .

Best Practices

• Load Considerations: Verify the maximum load capacity of the crossarm and suspension rods. Large trays may require multiple rods per crossarm for heavier installations.
• System Compatibility: Use components designed and tested together to ensure safety and structural integrity .
• Maintenance Access: Leave sufficient clearance above and around trays for cable installation and future maintenance.
• Compliance: Follow relevant standards such as BS EN 61537 for cable tray systems and BS 6946 for channel supports .

Additional Notes

• For small-sized trays, hoisting frames with a single suspension rod may be sufficient, but crossarms are preferred for larger or heavier installations .
• Center-hung tray supports can also be used for quick installation, but maximum load per hanger and spacing must be observed to prevent overloading . By following these guidelines, crossarm-supported cable trays can provide a safe, stable, and durable solution for industrial and commercial cable management.