How to install cable tray shafts

Proper installation of a cable tray shaft requires careful planning, secure support systems, adherence to standards, and ensuring clearances for cable routing and maintenance.

Planning and Preparation

Before installation, review the approved shop drawings to determine the layout, vertical and horizontal runs, and shaft entry/exit points. Ensure the area is cleared of obstructions and that civil and MEP clearances are obtained. Materials, including cable trays, ladders, fittings, and accessories, should be inspected for compliance with project specifications and stored horizontally on flat surfaces with timber supports to prevent damage.

Material Selection

Cable trays can be made from aluminum, stainless steel, galvanized steel, or pultruded fiberglass, depending on environmental conditions and corrosion resistance requirements. Aluminum offers excellent corrosion resistance, while stainless steel (AISI 316L) is suitable for highly corrosive environments. Galvanized steel provides economical protection against corrosion, and fiberglass trays offer high strength-to-weight ratios.

Support and Mounting

Vertical cable tray shafts require secure support systems capable of handling the weight of the trays and cables, including future additions. Supports should be spaced according to manufacturer recommendations and standards such as BS EN 61537 and BS 6946. Non-metallic supports may require special load considerations due to material properties and temperature effects.

Ensure that supports maintain proper alignment and allow for thermal expansion.

Installation Procedure

Mark the shaft routes according to approved drawings, ensuring vertical alignment and avoiding clashes with other services. Install the hanging system and supports first, verifying that they are level and securely anchored. Assemble and mount the cable trays in sections, connecting fittings and accessories as required.

Use appropriate fasteners and torque settings to maintain structural integrity. Maintain clearances for cable pulling, ventilation, and future maintenance. Avoid sharp bends and ensure smooth transitions between horizontal and vertical runs.

Install covers if required, especially in areas exposed to dust, debris, or mechanical impact.

Safety and Compliance

Cable trays are mechanical supports for cables, not walkways or ladders. Personnel should avoid standing on trays to prevent injury and damage. All installations should comply with NEMA VE2 guidelines and local electrical codes, including proper grounding and bonding.

Labeling and documentation of the installed system are recommended for maintenance and inspection purposes.

Inspection and Maintenance

After installation, inspect the shaft for proper alignment, secure fasteners, and absence of damage. Routine inspections should be part of the facility's maintenance schedule to ensure continued safety and performance. By following these steps, a cable tray shaft can be installed safely, efficiently, and in compliance with industry standards, ensuring reliable support for electrical and communication cables.