Vertical cable tray supports must secure cables at the top and at intervals not exceeding 1.5 meters to ensure stability, prevent sagging, and maintain system integrity.

Support Spacing and Placement

For vertical cable runs, cables should be secured at the top of the tray and every 1.5 meters along the vertical section to prevent undue mechanical strain and maintain proper alignment . This spacing ensures that the weight of the cables does not cause sagging or stress on terminations, which could compromise safety and performance . For horizontal runs, supports are typically placed at the start, end, and turns, and every 3 to 5 meters along straight sections .

Structural Considerations

Vertical supports must be strong enough to handle the total anticipated cable weight and maintain stability under mechanical loads . Common support methods include cantilever wall brackets mounted directly to walls or trapeze hangers for suspended installations . The material of the support system is usually steel or stainless steel, often with galvanization or other corrosion-resistant finishes for durability .

Fire Resistance and Safety

All cable supports, including vertical supports, should be fire-resistant to prevent premature failure in case of fire, in accordance with BS 7671 Clause 521.10.202 . Supports must also avoid obstructing access or egress routes to ensure safe evacuation and firefighting operations.

Additional Guidelines

• Binding and cable ties: When binding cables within the tray, ties should be spaced no more than 1.5 meters apart to maintain even tension and prevent cable movement .
• Tray clearance: Vertical trays should maintain a minimum distance of 0.3 meters from ceilings or obstructions, and the tray width should be at least 0.1 meters to allow proper airflow and heat dissipation .
• Load and fill rate: The cross-sectional fill of cables should not exceed 50% of the tray to prevent overheating and maintain structural integrity .

Summary

Proper vertical cable tray support involves securing cables at the top and every 1.5 meters, using structurally sound, fire-resistant materials, and ensuring adequate clearance and fill rates. Following these guidelines ensures mechanical stability, safety, and compliance with electrical standards while facilitating maintenance and future expansion.