Yes, cable trays are installed first, and then cables are laid into them following proper planning, support, and spacing guidelines.

Installation Sequence

1. Planning and Route Design Before any physical installation, the tray route should be carefully planned according to the site layout, clearance requirements, and cable separation needs. Approved shop drawings should be reviewed to ensure proper alignment, levels, and avoidance of clashes with other services .
2. Tray Selection and Preparation Choose the appropriate tray type—ladder, perforated, or solid-bottom—based on airflow, load, and cable type. Trays should be inspected for damage and stored properly before installation .
3. Mounting and Support Trays are mounted using brackets, hangers, or trapeze systems, with supports spaced typically between 1.5 to 3 meters depending on tray type and load. Proper alignment and leveling are critical to prevent sagging and ensure long-term stability .
4. Cable Installation Once the trays are securely installed, cables are laid in an organized manner. Key considerations include:
   • Avoiding excessive bending to prevent insulation damage
   • Maintaining proper spacing and identification markers for maintenance
   • Ensuring cable fill does not exceed 40% of tray capacity to prevent overheating
   • Securing cables at regular intervals to maintain order and safety
5. Compliance and Safety Installation should comply with local electrical codes and standards, such as NEMA, IEC, or CEC, and follow safety protocols to prevent injury or property damage . Fire-rated walls or floors require special attention to prevent fire spread through cable routes .

Best Practices

• Use a pre-determined layout plan to save time and reduce errors.
• Verify all materials and tools before starting work.
• Ensure adequate clearance for future maintenance and cable pulling.
• Center-hung tray supports can facilitate easier cable installation from both sides .
• Avoid mixing different brands of trays and fittings unless compatibility is confirmed . By following this sequence—installing the tray first, then laying and securing cables—you ensure a safe, organized, and code-compliant electrical installation that allows for efficient maintenance and long-term reliability.