Connection between sub-cable tray and main cable tray

Connecting a sub-cable tray to a main cable tray requires proper alignment, secure support, and compliant jointing to ensure safe and organized cable routing.

Planning and Preparation

Before installation, survey the site and review approved drawings to determine the route of both the main and sub-cable trays, ensuring adequate clearance from walls, equipment, and other structures ( ). Identify the type of trays (ladder, perforated, or solid-bottom) and the required fittings such as tees, bends, and reducers. Establish an elevation benchmark using a laser level or transit to maintain consistent tray height ( ).

Support Installation

Install supports for both main and sub-trays using wall-mounted brackets, floor stands, or ceiling hangers. Standard spacing is typically 1.5–3 meters, depending on tray type and load ( ). Ensure supports are level and aligned before fixing. For threaded rod hangers, pre-thread nuts and verify rod lengths to avoid delays during assembly ( ).

Tray Assembly and Connection

1. Position the main tray on its supports and secure it using coupler plates or tray connectors. Tighten joints to the recommended torque to maintain rigidity ( ).
2. Install the sub-tray by aligning it with the main tray at the connection point. Use a tee or side-entry fitting to join the sub-tray to the main tray, ensuring the joint is mechanically secure and level ( ).
3. Check bend radii for cables exiting the sub-tray to prevent sharp bends that could damage insulation ( ).
4. Secure the sub-tray to its supports, maintaining proper spacing and alignment with the main tray.

Cable Management

Lay cables neatly within both trays, using cable ties or straps to separate by voltage or function. Leave sufficient slack for thermal expansion and future maintenance ( ). Ensure that the sub-tray does not overload the main tray and that the combined load is within the tray's rated capacity.

Safety and Compliance

Follow local electrical codes (e.g., Canadian Electrical Code or NEC) and occupational safety procedures. Avoid drilling or cutting structural members without approval, and consult structural engineers if modifications are required ( ). Use appropriate personal protective equipment and lifting tools when handling heavy trays. By following these steps, the sub-cable tray can be safely and efficiently connected to the main cable tray, ensuring organized routing, mechanical stability, and compliance with electrical standards.