Installation of Sierra Leone Trough-Type Cable Tray Support Arms

Proper installation of trough-type cable tray support arms ensures structural stability, safe cable routing, and compliance with industry standards.

Planning and Preparation

Before installation, review the approved shop drawings to determine tray layout, support locations, and lengths of cable trays. Inspect all materials for damage and verify they match the approved submittal. Store trays horizontally on a flat surface with timber supports at intervals of approximately 1 meter to prevent deformation and protect from moisture and sunlight.

Ensure all tools, fasteners, and accessories are available and suitable for the environment.

Support Arm Placement

Support arms for trough-type cable trays should be positioned to bear the load of the tray and cables without exceeding the manufacturer's recommended span. Typically, supports are placed at the ends of trays, elbows, and at intervals along straight runs, avoiding placing connectors directly on supports or at the center of spans. For long runs, expansion connectors should be installed at building expansion joints or at intervals of 30 meters (100 ft) to accommodate thermal expansion.

Mounting Procedure

Attach the center tray hanger to the support structure, ensuring it is level and aligned with the tray path. Install spring nuts or bolts through pre-drilled holes in the tray bottom, typically 7/16” or 3/8” diameter, and secure with washers. Use vertical and horizontal pivot connectors inside the tray to allow angular adjustments up to 60° for alignment with structural members.

Maintain a minimum clearance of 300 mm (12”) above and to the side of the tray for accessibility and cable handling.

Material and Corrosion Considerations

Support arms and trays are commonly made of steel or stainless steel, with galvanization or other protective coatings to resist corrosion in humid or coastal environments. Aluminum or pultruded fiberglass may be used for lightweight or highly corrosive conditions. Ensure the selected material matches the environmental and mechanical load requirements.

Bonding and Grounding

All cable trays and support arms must be electrically bonded to maintain continuity and safety. Install bonding jumpers at expansion joints and ground trays at intervals of 15 meters (50 ft) and at both ends. Conduit drop-outs should also be bonded to the tray using compression lugs or grounding bushings.

Cable Handling

When pulling cables into the tray, use the conductor for pulling, not the insulation, and employ proper radius wheels to prevent damage. Secure cables with clamps or straps suitable for outdoor use and UV resistance to limit movement within the tray. Avoid using the tray to support rigging equipment during installation.

Final Checks

After installation, verify that all supports are secure, trays are level, and clearances are maintained. Inspect for proper bonding, grounding, and alignment with the approved drawings. Document any deviations and ensure compliance with local electrical codes and NEMA VE 2 standards.

By following these steps, Sierra Leone trough-type cable tray support arms can be installed safely, efficiently, and in compliance with industry standards, ensuring long-term reliability of the cable management system.