How to fix a vertical ladder-type cable tray

Vertical ladder-type cable trays should be securely mounted using appropriate wall or structural supports, with proper spacing, load considerations, and compliance with standards like BS EN 61537.

Mounting Principles

Vertical ladder trays are designed to support and route cables along walls or structural elements. They must be fixed using wall brackets, support brackets, or center-hung supports that are rated for the tray's load, including the weight of cables and any future additions ( ). The tray should not be used as a ladder for personnel, as it is intended solely for cable support ( ).

Support Spacing and Load

• Maximum support spacing depends on the tray type, material, and load. For heavy-duty ladder trays, spacing is typically around 3–3.6 meters per support, but this should be verified with the manufacturer ( ).
• Load capacity per hanger or bracket must be considered; typical values range from 318 kg to 340 kg per support ( ).
• Ensure that the tray is balanced and aligned vertically, with cables evenly distributed to prevent excessive bending or stress ( ).

Fixing Methods

1. Wall Brackets: Attach the tray to walls using brackets or cleats, ensuring the wall can bear the load. Drill holes as required and use bolts or anchors suitable for the wall material ( ).
2. Support Brackets: For vertical runs along structural steel or concrete, use adjustable support brackets or strut channels to secure the tray.
3. Center-Hung Supports: In some installations, vertical trays can be supported from overhead structures using threaded rods and clamps, allowing easier cable installation from both sides ( ).
4. Fittings and Accessories: Use vertical bends, T-pieces, and junction fittings to maintain smooth cable routing and prevent sharp bends that could damage cables ( ).

Safety and Standards

• Follow BS EN 61537 for cable tray systems and BS 6946 for channel supports ( ).
• Avoid cutting or drilling structural members without approval from the project engineer ( ).
• Ensure all components are compatible and tested together to maintain mechanical integrity and safety ( ).
• Maintain proper grounding and bonding of the tray system to prevent electrical hazards ( ).

Practical Tips

• Plan the vertical route carefully, considering cable entry and exit points.
• Use modular systems to allow future expansion or rerouting.
• Check deflection limits to ensure the tray does not sag under load ( ).
• Secure cables with banding or ties at intervals to prevent movement and strain ( ). By following these guidelines, vertical ladder-type cable trays can be installed safely, efficiently, and in compliance with industry standards, ensuring long-term reliability and protection for the cables they support.