Cable tray supports are typically placed every 1.5 to 3 meters for standard trays, with long-span or heavy-duty trays allowing up to 6 meters between supports.

Standard Support Spacing

For most standard cable trays, the distance between supports should be approximately 1.5 to 3 meters. This ensures that the tray maintains sufficient rigidity and prevents excessive deflection under the weight of the cables . The exact spacing depends on the tray material, load, and installation environment, including factors like vibration, wind, and temperature fluctuations .

Long-Span and Heavy-Duty Trays

Long-span or heavy-duty trays, which are constructed with thicker metal or reinforced materials, can support distances up to 6 meters (about 20 feet) between supports . These trays reduce the number of hangers required, saving labor costs, but they are more expensive due to the stronger construction. Always consult the manufacturer's load capacity chart to verify the maximum allowable span for your specific tray and cable load .

Additional Considerations

• Deflection Limits: After cable installation, the tray deflection should not exceed 1/200 of the span for standard trays, or 1/150 for spans ≥ 6 meters .
• Installation Environment: Outdoor installations, areas with mechanical stress, or high vibration may require closer support spacing .
• Vertical and Horizontal Runs: In vertical runs, supports should be placed to secure cables within 2 meters from the ground, and horizontal runs should avoid placing connections at mid-span .
• Code Compliance: NEC Article 392 requires that support spacing aligns with the manufacturer's instructions and load ratings, ensuring safe and compliant installations . By considering these factors, you can determine the optimal support spacing for your cable tray system, balancing safety, structural integrity, and cost efficiency.