How to install elbows in cable trays

Proper installation of elbows on cable trays ensures smooth cable routing, maintains minimum bend radius, and prevents damage to conductors.

Plan and Measure Before Installation

Before installing elbows, mark the exact location where the tray changes direction. Measure the required length and angle of the elbow to ensure it aligns with the overall cable tray route and avoids interference with other equipment or structural elements. Consider the minimum bend radius for the cables to prevent insulation damage or signal degradation, especially for fiber optic or control cables.

Select the Right Elbow Type

Cable tray elbows come in horizontal, vertical, and adjustable types. Choose the elbow that matches the tray type (ladder, ventilated trough, or solid-bottom) and the direction of the turn. For tight spaces, adjustable elbows can help achieve precise alignment without cutting or forcing the tray.

Cutting and Deburring

If a custom fit is required, measure and cut the tray section carefully using a hacksaw or angle grinder. Always deburr the edges to remove sharp metal that could damage cable insulation during installation.

Secure and Support Properly

Install the elbow on the tray supports using splice plates, bolts, or hold-down clips. Ensure the elbow is level and aligned with the adjoining tray sections. Maintain proper support spacing (typically 1.

5 to 3 meters depending on load and tray type) to prevent sagging or stress on the elbow. For vertical elbows, consider additional support brackets to handle the weight of cables.

Maintain Cable Organization

When laying cables through elbows, avoid overcrowding and maintain separation by voltage or function. Use cable ties or straps to secure cables inside the elbow, leaving enough slack for thermal expansion or future adjustments. Ensure that the bend radius inside the elbow is not exceeded to prevent conductor stress.

Grounding and Bonding

For metal trays, bond the elbow to the rest of the tray system to maintain electrical continuity and comply with NEC Article 392. Use proper bonding jumpers across the elbow section to ensure safety.

Final Checks

After installation, inspect the elbow and adjoining tray sections for alignment, secure fastening, and proper cable routing. Label the section if necessary for future maintenance or troubleshooting. By following these steps, elbows can be installed safely and efficiently, ensuring a durable and code-compliant cable tray system.