Cable tray support hangers should typically be spaced between 1.5 meters and 3 meters, depending on tray type, load, and installation conditions, in accordance with IEC 61537 and NEMA VE 2 standards.

Recommended Support Spacing

• Straight horizontal runs: Supports are generally installed every 1.5 to 3 meters. The exact spacing depends on the tray type (ladder, perforated, or solid-bottom), material, and the total cable load .
• Vertical runs: Supports should be placed at intervals not exceeding 1.5 meters to maintain stability .
• Concentrated loads: Extra supports are required near cable entry/exit points, bends, or where heavy cables drop in or out .
• Long-span trays: For specially reinforced trays, spans up to 6 meters may be possible, but these require thicker tray sides and careful load calculations .

Calculation Method

To determine the number of supports for a given tray length, the following formula is commonly used: Support Quantity = (Total Tray Length ÷ Support Spacing) + 1 For example, a 20-meter tray with 2-meter spacing requires 11 supports, including both ends .

Compliance and Safety Considerations

• Standards: Ensure compliance with IEC 61537 for mechanical strength, corrosion resistance, and electrical continuity, and NEC Article 392 for installation practices .
• Load capacity: Supports must handle the maximum expected cable load with an appropriate safety factor.
• Environmental factors: Outdoor, industrial, or corrosive environments may require galvanized, epoxy-coated, or stainless steel supports .
• Fire protection: In some installations, supports must meet fire-resistance ratings per IEC 60331 or NFPA standards .

Types of Supports

• Wall-mounted brackets: For horizontal trays along walls.
• Ceiling-hung supports (threaded rods, trapeze hangers): Common in indoor electrical rooms.
• Floor-mounted pedestals: For raised floors in substations or data centers.
• Cantilever brackets: For external or side support in narrow spaces . By following these spacing guidelines and standards, cable tray systems will maintain structural integrity, ensure safety, and provide long-term reliability.