Installation of ladder-type and trough-type cable trays

Ladder-type and trough-type cable trays can be connected using transition fittings, splice plates, and proper support alignment to ensure structural integrity and cable protection.

Steps to Connect Ladder and Trough Trays

1. Plan the Transition Location Identify the point where the ladder tray (with side rails and rungs) will meet the trough tray (ventilated or solid bottom). Ensure the transition is accessible for cable routing and maintenance, and that the support structure can handle the combined load of both trays . 2. Use a Transition Fitting or Adapter Manufacturers often provide transition fittings specifically designed to connect different tray types. If a pre-made fitting is unavailable, a custom adapter plate can be fabricated to align the ladder rungs with the trough bottom. The adapter should maintain the tray width and provide a smooth surface for cables to prevent snagging . 3. Align and Secure the Trays

• Ensure both trays are level and properly aligned.
• Use splice plates or flat connector plates to join the ladder side rails to the trough edges.
• Fasten with bolts, nuts, or rivets according to manufacturer specifications.
• Check that the connection is rigid and can support the expected cable load without excessive deflection . 4. Maintain Cable Support and Ventilation
• Ladder trays provide ventilation through rungs, while trough trays offer continuous support.
• At the transition, ensure cables are supported continuously to prevent sagging.
• Use cable ties or clamps to secure cables at the transition point, maintaining proper spacing and avoiding sharp bends . 5. Grounding and Bonding
• Both tray types must be bonded to the electrical grounding system.
• Ensure the transition fitting or splice plate maintains electrical continuity between the ladder and trough sections . 6. Inspect and Test
• After installation, inspect the connection for mechanical stability, alignment, and cable protection.
• Verify that the transition does not create pinch points or obstacles for cable pulling.
• Confirm compliance with NEC Article 392 and local electrical codes . By following these steps, ladder-type and trough-type cable trays can be safely and efficiently connected, ensuring both structural integrity and proper cable management.