How to add a cable tray layer

To add a cable tray layer, ensure proper vertical spacing, secure supports, and coordinate with existing trays and building services.

Planning and Preparation

Before adding a new layer, review the approved shop drawings to confirm the tray route, dimensions, and the number of layers allowed ( ). Check for potential clashes with HVAC ducts, fire pipes, or drainage systems, and resolve any conflicts with the project engineer. Ensure all materials for the new layer are available and approved for use.

Selecting Tray Type and Spacing

Choose a tray type suitable for the cables it will carry. For example, a basket tray is often used for structured cabling, while a solid-bottom tray is preferred for electrical circuits ( ). Maintain a minimum vertical distance of 30 cm between the new tray layer and the existing tray to prevent electromagnetic interference and allow proper airflow ( ).

Installing Supports

Install supports according to the tray type and load. Supports can be wall-mounted brackets or ceiling trapeze hangers. Standard support spacing is typically 1.

5 to 3 meters, depending on the tray size and weight of the cables ( ). Ensure the supports are level and aligned with the existing tray system.

Mounting the New Tray Layer

Measure and cut the tray sections to fit the designated route. Deburr edges to prevent cable damage ( ). Lift and place the tray onto the supports, ensuring it is level and properly aligned with the existing layer.

Secure the tray using hold-down clips, bolts, or couplers to prevent movement ( ). Join sections end-to-end with splice plates or connectors to maintain structural integrity.

Final Checks

After installation, verify that the new layer maintains the required clearances, is properly grounded, and does not interfere with other services. Conduct a visual inspection and ensure compliance with NEC Article 392 or local electrical codes ( ). By following these steps, you can safely and efficiently add a cable tray layer while maintaining proper spacing, support, and compliance with electrical standards.