Photovoltaic (PV) installations rely on specialized cables to ensure safe, efficient, and long-lasting power transmission from solar panels to inverters and the grid. Exposed to extreme weather, UV radiation, and high DC voltages, these cables must withstand harsh conditions for 25-30+ years. In 2025, with global solar capacity surging, choosing the right PV cables—compliant with standards like EN 50618 and TÜV 2PfG 1169—is critical for system reliability, safety, and performance optimization.

1. Introduction to PV Cables

PV cables primarily carry DC current between modules, strings, combiners, and inverters. They differ from standard power cables by requiring enhanced UV, ozone, and weather resistance, plus halogen-free flame retardancy for fire safety. Most are single-core, tinned copper with cross-linked insulation, rated for 1.5-2 kV DC.

2. Key Requirements for Solar Cables

• UV and weather resistance for rooftop/ground-mount exposure.
• Operating temperature -40°C to +90°C (120°C overload).
• Halogen-free, low-smoke (LSZH) for reduced toxicity.
• Flame retardant (IEC 60332-1) and resistant to ozone/acids.
• High DC voltage withstand and low conductivity loss.
• Mechanical robustness against abrasion and rodent damage.

3. Governing Standards in 2025

The primary European standard is EN 50618 (H1Z2Z2-K) for PV DC cables, replacing TÜV 2PfG 1169/08.2007 while maintaining compatibility. It specifies construction, testing (aging, shrinkage, ozone), and marking. Globally, IEC 62930 and UL 4703 (PV Wire) are recognized, with harmonization ongoing for international projects.

4. Types and Construction

Standard PV cable: Tinned copper conductor (Class 5 flexible), XLPE insulation, XLPE or halogen-free sheath, often dual-layered. Common designation: H1Z2Z2-K (halogen-free, cross-linked insulation/sheath).

5. Cable Sizing and Selection

Size based on current, voltage drop (≤3% recommended), ambient temperature, and routing. Use 4-6 mm² for strings, 10-35 mm² for array-to-inverter.

6. Installation Best Practices

• Use UV-resistant ties/clips; avoid sharp bends (min 5x diameter).
• Separate DC/AC cables; maintain polarity.
• Employ rodent-proof conduits in ground mounts.
• Ensure proper MC4 or compatible connectors (IP67+).
• Allow thermal expansion with loops.

7. Applications in PV Systems

Module-to-module strings, array combiners, inverter feeds, and battery storage links. AC side uses standard cables (e.g., NYY or flexible for trackers). In large-scale plants, aluminum conductors gain traction for cost savings in main runs.

8. Final Thoughts

Cables for photovoltaic installations are engineered for decades of reliable service under extreme conditions. Adhering to EN 50618/H1Z2Z2-K ensures safety, minimal losses, and compliance in 2025's booming solar market. Proper selection and installation maximize system yield and longevity—critical for sustainable energy returns.

For high-quality PV cables meeting EN 50618 and global standards, contact Henan Province Jianyun Cable Co., Ltd. for customized solutions and competitive quotes.