Supports for vertical installation of cable trays

Vertically installed cable trays require secure support using brackets, riser clamps, or wall-mounted supports at intervals recommended by standards and manufacturers to ensure stability and cable safety.

Types of Supports

For vertical cable trays, several support options are commonly used:

• Wall or structural brackets: Fixed to walls or steel structures to hold the tray securely. These can be single or double brackets depending on load and tray width .
• Riser clamps or riser supports: Designed to grip the tray and maintain alignment in vertical runs, preventing lateral movement .
• Suspended supports: In some cases, vertical trays may be supported from overhead structures using threaded rods and hangers, especially for long risers .
• Splice connectors: Used at joints to maintain structural integrity and prevent sagging .

Support Spacing

The spacing of supports for vertical cable trays depends on tray type, material, and load:

• Steel trays (6-inch depth, 14-gauge hot-dip galvanized) can often be self-supporting up to 20 feet, but intermediate supports are recommended for stability .
• IEEE Std 525-1992 suggests that vertical runs should be supported at intervals sufficient to keep all cables fully within the tray and secured, with exact spacing often determined by the tray manufacturer .
• General practice: For typical vertical risers, support spacing ranges from 4 to 6 feet for standard steel trays, but heavier loads or longer runs may require closer intervals . Always consult the manufacturer's specifications for exact spacing.

Installation Best Practices

• Ensure all supports are rated for the combined weight of the tray and cables, including any potential short-circuit forces .
• Use proper mounting hardware compatible with the tray type; cable ties alone are insufficient for vertical installations .
• Maintain alignment and plumb of the tray to prevent cable stress and ensure proper routing.
• Consider environmental factors such as corrosion, temperature, and vibration when selecting materials and finishes .
• For multi-directional trays, ensure that vertical supports are compatible with horizontal transitions and bends .

Summary

Vertically installed cable trays must be supported using brackets, riser clamps, or wall-mounted supports at intervals recommended by standards and manufacturers. Proper support ensures mechanical stability, prevents cable displacement, and maintains compliance with safety and electrical installation standards. Always follow manufacturer guidelines and applicable standards such as IEEE 525-1992 and BS EN 61537 for optimal performance and safety .