National Standard Cable Tray Model Thickness

Cable tray thickness is governed primarily by NEMA VE 1 for metal trays and UL 568 for nonmetallic trays, with thickness determined by tray type, material, load class, and span.

Metal Cable Trays

For metal cable trays (steel or aluminum), the NEMA VE 1 standard specifies minimum material thicknesses based on tray type and load/span requirements. Typical guidelines include: Ladder and ventilated trays: Steel trays generally range from 1. 5 mm to 3 mm (14–12 gauge) depending on width, span, and load class.

Aluminum trays are slightly thicker for equivalent strength due to lower modulus of elasticity. Solid-bottom trays: Require slightly greater thickness than ventilated trays to maintain rigidity and prevent sagging. Load/span classification: NEMA VE 1 defines light, medium, and heavy-duty classes, with thicker materials required for longer spans or higher cable loads.

The thickness selection ensures compliance with structural integrity, heat dissipation, and cable fill requirements. Pre-galvanized or hot-dip galvanized steel trays may have slightly different thicknesses to account for corrosion protection.

Nonmetallic Cable Trays

For nonmetallic trays (fiberglass or composite), UL 568 and the former NEMA FG-1 standard provide guidance: Thickness is determined by tray width, span, and load rating. Fiberglass trays are designed to resist corrosion and maintain structural strength, often requiring thicker walls than metal trays for equivalent load capacity.

U

L 568 specifies testing for deflection and load-bearing performance rather than a fixed thickness, so manufacturers provide thickness tables based on tray type and span.

International Standards

The IE

C 61537 standard harmonizes cable tray requirements internationally, including: Material thickness for metal and nonmetallic traysLoad/span testingConstruction and finish requirements for corrosion resistance and mechanical strength.

Practical Considerations

Always select tray thickness according to load class, span, and environmental conditions. Verify compliance with local electrical codes (NEC in the U. S., CEC in Canada, or national adaptations of IEC standards).

Manufacturers provide thickness tables for each tray type, which should be referenced during design and installation. In summary, cable tray thickness is not a single fixed value; it depends on material, tray type, span, and load class, with NEMA VE 1 and UL 568 serving as the primary references for U. S. installations, while IEC 61537 provides international guidance.