Standards for Galvanized Cable Trays

Galvanized cable trays must comply with IEC 61537, NEMA VE 1, UL 568, and specific galvanizing standards such as GB/T 13912-2020 for hot-dip coatings.

General Cable Tray Standards

1. IEC 61537 – This international standard specifies requirements for metal cable tray systems, including mechanical strength, corrosion resistance, electrical continuity, fire performance, ventilation, and installation compatibility. It applies to steel, stainless steel, aluminum, and other metallic trays, ensuring safety and durability across various environments .

2. NEMA VE 1 – Defines manufacturing requirements for metal cable trays (ladder, channel, wire mesh, solid bottom) and associated fittings in accordance with the National Electrical Code (NEC). It includes load/span class designations and installation guidelines .

3. UL 568 – Covers performance requirements for safe application of fiberglass and metal cable trays, including testing for mechanical and environmental performance .

Galvanizing Standards

Galvanized cable trays can be produced using two main processes, each with distinct standards and corrosion resistance characteristics :

1. Electro-Galvanized (Electroplated) Trays

   • Zinc is deposited onto steel via electrolysis.
   • Produces a thin, bright, uniform coating with moderate corrosion resistance.
   • Primary Standard: GB/T 26941.1-2011 “Cable Trays – Part 1: General Requirements.”

2. Hot-Dip Galvanized Trays

   • Steel is submerged in molten zinc, forming a zinc-iron alloy layer and a pure zinc layer.
   • Provides thick, highly adherent coating with superior corrosion resistance, suitable for harsh environments (outdoors, coastal, heavy industry).
   • Primary Standard: GB/T 13912-2020 “Metallic coatings – Hot dip galvanized coatings on fabricated iron and steel articles – Specifications and test methods.”
   • Coating Requirements: For tray sheet metal thickness of 1.5–3 mm, the local zinc thickness must be ≥45 µm, corresponding to a coating mass of ≥325 g/m² .

Additional Considerations

• Material Thickness: Side and base plates typically range from 1.5 mm to 3 mm.
• Environmental Suitability: Hot-dip galvanizing is preferred for outdoor, marine, or industrial environments due to superior corrosion protection.
• Compliance Verification: Manufacturers often provide CE marking or third-party certification (UL, IMQ, LCIE) to demonstrate compliance with applicable standards .

In summary, galvanized cable trays must meet both general cable tray standards (IEC 61537, NEMA VE 1, UL 568) and specific galvanizing standards (GB/T 26941.1-2011 for electro-galvanized, GB/T 13912-2020 for hot-dip galvanized) to ensure mechanical integrity, corrosion resistance, and safe installation.