Requirements for Custom-Made Cable Trays

Custom-made assembled cable trays must comply with international standards, mechanical and electrical requirements, material specifications, and installation best practices to ensure safety, durability, and performance.

Standards and Compliance

Custom cable trays should adhere to IEC 61537, which governs metallic cable tray systems, including steel, stainless steel, and aluminum trays, ensuring mechanical strength, corrosion resistance, electrical continuity, and fire performance. In the U. S., compliance with NEC Article 392 and NFPA 70 is essential for grounding, bonding, and fill capacity.

Manufacturers must also follow ASTM and NEMA specifications for materials and coatings, such as ASTM A653 for galvanized steel and NEMA VE 1/VE 2 for metallic tray systems.

Material and Construction Requirements

Materials: Steel, stainless steel, or aluminum alloys (e.g., Aluminum Association Alloy 6063 for extrusions, 5052 for fabricated parts) with appropriate corrosion-resistant coatings. Mechanical Strength: Trays must withstand cable weight, environmental loads, and external pressure, validated through load testing. Corrosion Resistance: Coatings or material selection must suit the environment, including marine, chemical, or outdoor conditions.

Fire Resistance: Trays should maintain structural integrity under high temperatures, especially in critical facilities. Electrical Continuity: Metallic trays must provide a reliable grounding path, with bonding jumpers used where mechanical connections are insufficient.

Design and Installation Considerations

Tray Types: Ladder, trough, solid bottom, channel, or wire mesh, selected based on cable type, load, and environmental conditions. Ventilation and Fill Ratio: Proper perforation and spacing prevent overheating; NEC recommends keeping tray fill at 50% or less for airflow and future expansion. Supports and Accessories: Include bends, tees, elbows, drop-outs, splice plates, and covers to maintain mechanical integrity and routing flexibility.

Cable Protection: Rounded edges, smooth surfaces, and proper rung spacing (typically 150–230 mm) prevent cable damage and maintain minimum bend radius. Storage and Handling: Trays must be delivered and stored in clean, dry conditions to avoid damage before installation.

Best Practices

Verify compliance with local electrical codes and project specifications. Ensure mechanical and electrical continuity at all splice points. Select materials and finishes appropriate for the installation environment.

Maintain accessibility for inspection, maintenance, and future cable additions. Use proper grounding and bonding techniques to prevent shock hazards and equipment failure. By following these requirements, custom-made assembled cable trays will provide safe, durable, and efficient cable management suitable for industrial, commercial, and utility installations.