Ground cable trays are manufactured by cutting, shaping, forming, and treating metal to create durable, NEC-compliant structures that can serve as both cable supports and grounding conductors.

Manufacturing Process

1. Material Selection and Cutting Cable trays are typically made from steel, aluminum, or fiberglass-reinforced plastic (FRP) depending on load requirements and environmental conditions. The raw material is cut to the required dimensions for the tray type, whether ladder, solid bottom, perforated, or trough ( ).
2. Forming and Assembly After cutting, the tray is bent, welded, or riveted to form the structure. Ladder trays feature side rails connected by rungs for ventilation and high-load support, while solid bottom trays provide full coverage for cable protection. Perforated trays allow heat dissipation, and trough trays offer secure storage for outdoor or high-equipment areas ( ).
3. Surface Treatment To enhance durability and prevent corrosion, trays undergo galvanization (zinc coating) or powder coating, which provides resistance to rust and environmental damage ( ).

Grounding Considerations

Metallic cable trays can serve as Equipment Grounding Conductors (EGC) if installed according to NEC Article 392 and Article 250.96. Each tray section should be bonded using grounding clamps, and insulated conductors are recommended in aluminum trays to prevent electrolytic corrosion. Proper grounding ensures safety under fault conditions and maintains electrical continuity ( ).

Compliance and Installation

• NEC Standards: Only tray-rated cables should be installed, with proper separation between power and data cables to prevent interference. Fill limits must be observed (40% for power cables, 50% for control cables) ( ).
• Clearances: Maintain at least 12 inches of vertical clearance above trays for maintenance access ( ).
• Prohibited Areas: Cable trays should not be installed in hoistways or enclosed spaces ( ).

Summary

The production of ground cable trays involves material preparation, forming, assembly, and surface treatment, with careful attention to grounding and NEC compliance. Properly manufactured and installed trays provide both mechanical support for cables and safe grounding paths, ensuring long-term reliability in industrial, commercial, and data center environments.