Positioning and Installation of Photovoltaic Cable Trays and Supports

Installing PV cable trays and supports requires careful planning, proper grounding, correct spacing, and adherence to electrical standards to ensure safety and long-term system reliability.

Planning and Design

Before installation, map out the cable tray routes from solar panels to inverters, considering rooftop layout, obstacles, and weight distribution. Use different tray sizes to optimize space and avoid overfilled or underutilized trays. Ensure the design accounts for mechanical load, thermal expansion, and environmental exposure such as UV, rain, and wind .

Selecting Cable Trays and Supports

• Material: Choose corrosion-resistant materials like galvanized steel or aluminum for outdoor PV systems .
• Type: Open trays are ideal for heavy DC cables and high-temperature regions, while partially ventilated trays protect AC and communication cables from dust and moisture .
• Certification: Ensure trays meet NEMA VE1/CSA C22.2 #126.1 standards for metallic raceways and comply with NEC 690.31(C) for PV conductor support .

Installation Steps

1. Vertical Trays:
   • Install vertical trays on the far left side of the planned array.
   • Mount over the entire length with a 300mm gap from top and bottom.
   • Secure to counter-laths with screws spaced 150–200mm apart .
2. Horizontal Trays:
   • Install under junction boxes every fourth panel.
   • Maintain 200mm clearance from the far right side.
   • Secure with screws at 150–200mm spacing.
3. Grounding and Electrical Continuity:
   • Connect all trays to a 16mm² ground wire.
   • Use connectors at tray junctions to ensure electrical continuity.
   • Verify grounding connections and check for sharp edges that could damage cables .
4. Cable Securing:
   • Use clips or supports no more than 55 inches apart and within 12 inches of cable entry points to comply with NEC requirements .
   • Avoid overfilling trays to prevent conductor damage and maintain airflow.

Final Checks

• Confirm mechanical stability of all trays and supports.
• Verify electrical continuity and proper grounding.
• Ensure correct spacing and secure attachment of all screws.
• Inspect for sharp edges or potential cable damage points .

Maintenance Considerations

• Regularly inspect trays for corrosion, loose screws, or sagging.
• Ensure cables remain properly supported and ventilated to prevent overheating.
• Plan for easy access to junction boxes and inverters for future maintenance . By following these steps, PV cable trays and supports will provide safe, durable, and code-compliant routing for all solar system cables, ensuring long-term performance and reduced maintenance costs.