In a photovoltaic power generation system, a photovoltaic cable is a key supporting wire that ensures the long-term safe and stable power generation of the power station. Most users tend to confuse photovoltaic cables with ordinary power cables, as there is a significant difference in performance and application scenarios between the two. This article provides a concise explanation of the definition, structure, core advantages, model standards, and application scenarios of photovoltaic cables, helping you quickly understand the core knowledge of photovoltaic-specific cables.
★. What is a photovoltaic cable?
A photovoltaic cable (PV cable) is a special weather-resistant cable used on the DC side of a photovoltaic power generation system. It is mainly used to transmit the direct current generated by photovoltaic modules and is suitable for outdoor and open-air complex working conditions. It can withstand exposure to sunlight, high and low temperatures, humidity, salt fog, etc., and can last for 25 years, providing an important guarantee for the stable operation of the photovoltaic power station.
It is mainly used for connecting photovoltaic modules, connecting modules to combiner boxes, and combiner boxes to inverters; the AC side output of the inverter does not require a photovoltaic cable and can use regular power cables instead.
★. Core structure design of photovoltaic cables
Photovoltaic cables adopt a double-layer special structure design, with greater flexibility and durability than ordinary cables. The structure is simple and the performance is reliable:
- Tin-plated soft copper conductor: Made of multiple strands of tin-plated soft copper wire twisted together, with good conductivity and low transmission loss. The tin plating process can effectively resist oxidation and corrosion, and the wire is flexible and easy to bend, suitable for various on-site wiring needs.
- Double-layer irradiation cross-linked insulation sheath: Made of halogen-free, low-smoke, flame-retardant polyolefin material, processed by irradiation cross-linking technology, fundamentally solving the problem of ordinary PVC cables aging, cracking, and brittleness in outdoor environments, and having high-strength insulation, weather resistance, and flame retardancy.
★. Core advantages of photovoltaic cables
Photovoltaic cables are special cables for photovoltaic power stations, and their core advantages are suitable for outdoor harsh environments and cannot be replaced by ordinary cables:
- Weather-resistant and anti-aging, with a lifespan of up to 25 years: Possessing excellent resistance to ultraviolet rays, ozone, and high and low temperatures, the working temperature range is -40°C to +90°C, suitable for various scenarios such as rooftops, coastal areas, deserts, and plateaus, and matching the design cycle of the photovoltaic power station with its lifespan.
- High-voltage insulation, stable and safe power transmission: Mainstream specifications support DC 1500V direct current high voltage, suitable for high-voltage networking of large photovoltaic power stations, with stable insulation performance, less leakage and breakdown, and low power transmission loss, effectively reducing the operational risks of the power station.
- Halogen-free and flame-retardant, safe and environmentally friendly: Made of low-smoke, halogen-free flame-retardant material, it extinguishes fire on its own and has no toxic smoke, effectively preventing the spread of fire and significantly improving the fire safety level of the photovoltaic power station.
- Corrosion-resistant and wear-resistant: Can resist salt fog, acid and alkali, and rain erosion, with strong mechanical wear resistance, and is not prone to damage during long-term outdoor laying, suitable for long-term outdoor operation conditions.
★. Main models and industry standards
Currently, two mainstream models are commonly used in domestic and international photovoltaic projects, suitable for different market certification requirements:
- PV1-F: A domestic standard model with stable performance and high cost-effectiveness, widely used in residential, commercial, and ground photovoltaic power stations.
- H1Z2Z2-K: An international standard model with TÜV authoritative certification and in line with EU standards, is the preferred model for overseas photovoltaic projects and export. Industry uniform standards: Red represents the positive DC pole, and black represents the negative DC pole. The wiring is clear, facilitating construction and later maintenance and repair.
★. Photovoltaic cable vs ordinary cable (core differences)
In engineering, most lines are aging, leaking, or tripping due to the incorrect use of ordinary cables. The core differences between the two are very clear:
- PVC wires are only suitable for indoor and mild environments and are prone to aging, cracking, and insulation failure when used outdoors, with a lifespan of only 2-3 years, and are strictly prohibited from being used in the DC circuits of photovoltaic power stations.
- Photovoltaic cables are specially designed outdoor special cables for photovoltaic DC applications. They have undergone rigorous weather resistance, flame retardancy, and aging tests and can be used for a long time in complex outdoor conditions, making them essential for the safe and long-term operation of power stations.
★. Main application scenarios
- Distributed photovoltaic power stations on household rooftops and industrial/commercial rooftops;
- Large-scale ground-based photovoltaic power stations, mountainous and desert photovoltaic bases;
- Photovoltaic projects in complex conditions such as coastal, high-altitude, and dusty areas;
- DC-side line laying for photovoltaic energy storage systems.
