Photovoltaic cable trays and trunking

Photovoltaic cable trays and trunking are essential systems for organizing, protecting, and supporting DC, AC, and communication cables in solar installations, ensuring safety, durability, and efficient maintenance.

Purpose and Importance

Cable trays and trunking in PV systems provide mechanical support, protection, and organized routing for cables running from solar panels to inverters or combiner boxes. They prevent cable sagging, reduce thermal load, protect against UV exposure, moisture, pests, and mechanical damage, and simplify inspection and maintenance, which is critical for systems designed to operate outdoors for 25–30 years .

Types of Cable Management

1. Open Cable Trays: These are ventilated channels where cables are visible. They allow strong airflow, reducing heat buildup, and are ideal for heavy DC cables and high-temperature regions. Open trays support long spans of 2–3 meters without deformation .
2. Closed Trunking: These have a snap-on lid providing full UV and weather protection, suitable for sensitive AC or communication cables, especially in inverter rooms or desert solar farms .

Materials

• ZAM Steel: Excellent corrosion resistance, ideal for coastal or industrial sites .
• Hot-Dip Galvanized (HDG) Steel: Durable and cost-effective, suitable for large utility-scale projects .
• Aluminum: Lightweight, rust-free, and preferred for rooftop or carport installations .
• Stainless Steel: Used in harsh environments for maximum durability .

Design and Installation

• Cable trays are typically C-channel or U-channel profiles with perforated bases for ventilation and secure cable bundling .
• Sections are joined end-to-end using splice plates and carriage bolts, and mounted directly onto solar racking rails .
• Accessories like 90° elbows, T-junctions, and end caps allow flexible routing and secure cable termination .
• Proper installation ensures no tight bends, reducing the risk of insulation damage and maintaining system reliability .

Benefits

• Enhanced cable protection from environmental and mechanical hazards .
• Improved airflow and heat dissipation, reducing cable overheating .
• Simplified maintenance and inspection, allowing easy troubleshooting and future expansion .
• Long-term system reliability, minimizing power losses and safety risks .

Applications

• Ground-mounted solar farms: Open trays for long DC cable runs with high load-bearing capacity .
• Rooftop installations: Lightweight aluminum trays for easy handling and minimal roof load .
• Inverter rooms or control buildings: Closed trunking for sensitive AC and communication cables . In summary, selecting the right photovoltaic cable tray or trunking system involves considering cable type, environmental exposure, load requirements, and installation location. Properly designed and installed systems enhance safety, reduce maintenance costs, and extend the operational life of solar power installations .