100MW Solar PV Power Plant Cable Sealing Protection Project

IP68 Cable Gland Application in Photovoltaic DC Systems

1. Project Background

This project is part of China’s national “Desert, Gobi, and Arid Region” large-scale renewable energy development strategy. The power plant generates approximately 170 million kWh annually.

Located in a high-altitude desert region, the site experiences extreme environmental conditions, including day-night temperature differences exceeding 40°C, average annual wind speeds of 6.5 m/s, and frequent sandstorms.

The plant includes 32 combiner boxes, each connecting 16 PV strings, with a maximum DC voltage of 1500Vdc. Reliable cable entry sealing in outdoor junction boxes and combiner boxes is critical to ensuring long-term stable operation.

• Customer: State-owned renewable energy developer subsidiary

• Project Scale: 100MW ground-mounted photovoltaic power plant

• Location: Ulanqab, Inner Mongolia

• Completion Time: November 2024

2. Application Scenarios and Challenges

2.1 Application Scenarios

• Cable entry sealing from PV strings to DC combiner boxes (total 4096 entry points)

• Power cable sealing from combiner boxes to DC distribution cabinets

• High-voltage connector cable protection in energy storage systems (2 × 10MWh battery cabinets)

• DC input cable sealing for outdoor inverters

2.2 Key Challenges

• Extreme Climate Conditions:
  Temperatures ranging from -30°C to +75°C (module surface), causing standard seals to crack and fail

• Sand and Dust Ingress:
  In desert environments, sealing below IP67 showed approximately 15% dust ingress within two years

• UV Degradation:
  High-altitude UV exposure caused conventional plastic materials to become brittle within two years

• Thermal Cycling Stress:
  Daily temperature fluctuations of 40°C led to sealing ring elasticity degradation

2.3 Key Technical Requirements

• Protection Rating: IP68

• Material: UV-resistant PA66 nylon + EPDM & silicone composite sealing ring

• Operating Temperature: -40°C to +100°C (continuous)

• UV Resistance: Passed UV8 weathering test (1000 hours)

• Thread Types: M16 / M20 / M25 / G1/2" / G3/4"

• Flame Retardant Rating: UL94 V-0 (self-extinguishing)

• Certifications: TUV, CE, RoHS, UL

Service Life: 25 years for outdoor applications

3. Product Configuration

4. Cable Gland Solution

After technical evaluation and on-site assessment, an optimized cable sealing solution was implemented, centered on IP68-rated UV-resistant cable glands designed for photovoltaic and outdoor energy applications.

These cable glands were applied across critical cable entry points in combiner boxes, inverter interfaces, and energy storage systems, ensuring long-term sealing performance under extreme environmental conditions.

Key Advantages of the Cable Gland Solution

• IP68 Waterproof and Dustproof Protection
  Prevents moisture and sand ingress even in desert environments with frequent storms

• UV-Resistant Material Design
  PA66 nylon with UV-resistant formulation ensures long-term durability under high solar radiation

• Thermal Stability and Elastic Sealing
  Composite sealing rings maintain elasticity under extreme temperature cycling

• Long-Term Outdoor Reliability
  Engineered for a 25-year service life in photovoltaic applications

• High Safety and Compliance
  Meets international standards including TUV, UL, and flame-retardant requirements

Supporting Services

• Product testing reports (IP68, UV resistance, flame retardancy)

• Participation in engineering design and drawing review

• On-site installation training (8 workers, 2 days)

• 25-year performance warranty commitment based on project requirements

5. Results and Customer Feedback

After installation and commissioning, the project achieved excellent operational stability with no sealing failures or electrical faults related to cable entry points.

“After comparing five suppliers, we selected this solution due to its UV-resistant PA66 material, which performs reliably under strong high-altitude UV exposure. After one year of operation, all 4096 cable entry points recorded zero leakage alarms, and sealing elasticity remained stable. Complete TUV certification documentation also supported EPC cost control.”
— Engineering Procurement Manager

Performance Results

6. Conclusion

This project demonstrates the critical role of high-performance cable glands in photovoltaic power systems, particularly in extreme outdoor environments where UV exposure, temperature variation, and dust ingress are significant challenges.

For solar PV plants, energy storage systems, and other renewable energy infrastructure, selecting the right cable gland is essential to ensuring long-term system reliability, safety, and efficiency.

Reliable Cable Sealing for Solar and Energy Storage Systems

For demanding photovoltaic and energy storage applications requiring UV resistance, long service life, and certified performance, YDT delivers cable gland solutions engineered for durability, environmental resistance, and global project standards.