Unlike traditional power cables, photovoltaic (PV) cables are exposed to outdoor environments for long periods. They must withstand UV radiation, temperature cycles, humidity, and electrical load at the same time. Therefore, there is a clear engineering logic in both cable classification and material selection.
In this context, PV cable materials have become a key factor that affects long-term cable reliability. Among them, crosslinked polyolefin materials have become the mainstream solution.
This article starts from the main types of PV cables. Based on real engineering applications, it analyzes the structure features and service conditions of different cables. It also explains the differences and selection logic of irradiated crosslinked polyethylene (XLPE) and silane crosslinked polyethylene in PV cable materials.
In a complete PV power system, cables in different positions have different functions.
Based on application scenarios and structure differences, PV cables can be divided into the following types:
PV DC cables are mainly used to connect PV modules and to connect modules to combiner boxes. They are one of the most widely used cable types in PV systems.
In real projects, these cables usually operate under DC voltage for a long time. The common rated voltage is 1000V DC or 1500V DC. The conductor cross-section is usually between 4mm² and 10mm². Among them, 4mm² and 6mm² are the most common sizes.
From a structural point of view, PV DC cables usually use a single-core design. The conductor is often tinned copper to improve oxidation resistance. The insulation thickness is usually between 0.5 mm and 0.8 mm. The sheath thickness is usually between 0.6 mm and 1.0 mm. The overall outer diameter is usually controlled between 5 mm and 8 mm.
Since PV DC cables are exposed to outdoor conditions for a long time, the materials must have strong UV resistance, heat resistance, and long-term electrical stability. Therefore, in PV cable material systems, this type of cable usually uses stable crosslinked polyolefin materials.
Common Materials:
both insulation and sheath can use 125℃ irradiated crosslinked polyolefin materials (irradiated XLPE).
Silane crosslinked polyethylene materials of the same grade can also be used.
These cables are mainly inverter output cables. They are used to transmit converted AC power to the grid or transformer.
The rated voltage is usually 0.6/1kV AC or higher. The conductor cross-section is large, ranging from 16 mm² to 240 mm², depending on system capacity and transmission distance.
In terms of structure, these cables are usually multi-core cables and may include filling structures and sheath layers. The insulation thickness is usually between 0.8 mm and 2.0 mm. The sheath thickness is usually from 1.0 mm to more than 3.0 mm.
These cables are often installed in cable trenches or cable trays. The materials must not only have basic electrical performance, but also meet flame retardant, low smoke, and mechanical strength requirements. Therefore, low smoke halogen-free cable materials are widely used in this type of PV cable.
Common materials:
both insulation and sheath can use 125℃ low smoke halogen-free irradiated crosslinked polyolefin materials.
Silane crosslinked polyethylene materials of the same grade can also be used.
These cables are also called PV tray cables. They are used to connect combined PV strings to inverters and are important DC transmission cables.
The working voltage is usually 1000V DC or 1500V DC. Because the current is high, the conductor cross-section is larger than module cables, usually between 6 mm² and 35 mm². Common sizes include 10 mm², 16 mm², 25 mm², and 35 mm².
In terms of structure, these cables are mostly single-core, but in some projects, dual-core structures are used to improve installation efficiency. The insulation thickness is usually between 0.7 mm and 1.2 mm. The sheath thickness is between 0.8 mm and 1.5 mm. The overall diameter is about 8 mm to 20 mm.
In design, these cables focus more on current carrying capacity and thermal stability. Therefore, in PV cable material selection, crosslinked polyolefin materials with stable crosslinking are preferred.
Common materials: both insulation and sheath can use 90℃ flame retardant irradiated crosslinked polyethylene materials.
With the growth of energy storage systems in PV plants, storage cables are becoming important. These cables are used between battery systems and converters. The working voltage can exceed 1000V DC. The conductor cross-section ranges from 10 mm² to 120 mm².
The working conditions are similar to high voltage DC cables, but the requirements for thermal stability and long-term aging are higher. Therefore, high-grade crosslinked polyolefin materials are used in PV cable material systems.
Common materials:
125℃ irradiated crosslinked polyethylene materials for PV energy storage cables.
In large ground-mounted PV plants, collection cables and grid connection cables are used for power transmission. They are among the highest load cables in the system. These cables are usually medium or high voltage, and the conductor cross-section can reach 240 mm² or even higher. The structure is complex and may include shielding and armoring.
In material selection, these cables must have strong electrical performance, mechanical strength, and environmental resistance. Therefore, low smoke halogen-free cable materials and crosslinked polyolefin materials are often used together.
Common materials: low smoke halogen-free polyethylene cable materials and low smoke halogen-free irradiated crosslinked cable materials.
In PV cable systems, crosslinked polyethylene / crosslinked polyolefin materials are the core materials.
Among them, irradiated XLPE and silane crosslinked XLPE are the most widely used technologies.
Irradiated XLPE (irradiated crosslinked polyethylene) forms crosslinking through electron beam radiation. After extrusion, the material enters irradiation equipment and forms a stable three-dimensional network under high energy beams. This material is a typical crosslinked polyolefin system.
This method has high crosslinking uniformity and stable performance. It is an important PV cable material for high-end applications.
In PV cables, irradiated XLPE is mainly used in:
First, insulation layers of PV module cables and string cables. It can keep stable electrical performance under long-term DC field and high temperature.
Second, high-end PV cables that need certifications such as TÜV, EN50618, IEC62930, and 2PFG1169. As a key PV cable material, irradiated XLPE shows strong consistency and long-term aging performance.
In addition, it is suitable for thin wall design. It can keep good strength while controlling insulation thickness. However, this material requires irradiation equipment, so it is more suitable for large-scale production.
Silane crosslinked XLPE is a chemical crosslinking system and is also part of crosslinked polyolefin materials.
In production, silane groups are grafted onto polyethylene chains. After extrusion, crosslinking is completed through moisture reaction. This process does not need irradiation equipment, so it can be done on standard extrusion lines and offers high flexibility.
In PV cables, silane crosslinked XLPE is mainly used in:
First, multi-specification cable production. As a flexible PV cable material, it is suitable for small to medium batch production.
Second, sheath layer applications. It provides stable mechanical performance and environmental resistance for outdoor use.
Third, cost-sensitive projects. Compared with irradiated systems, it has advantages in equipment cost and processing cost.
In terms of performance, it also has good heat resistance and aging resistance. With proper design, it can meet long-term operation requirements of 1000V or 1500V systems.
In real projects, PV cables rarely rely on only one material system. Instead, materials are selected based on cable type and application. This is the core logic of PV cable material selection.
For example, in DC cables, irradiated XLPE is often used as insulation to ensure stable performance. The sheath can use either irradiated or silane crosslinked materials based on cost and processing conditions.
In string cables and inverter cables, due to higher current and thermal load, materials with more stable crosslinking are preferred to ensure long-term reliability.
In AC output and grid cables, material selection focuses more on flame retardant performance, mechanical strength, and installation conditions. Therefore, low smoke halogen-free cable materials are used together with crosslinked polyolefin materials.
Overall, PV cable materials are developing based on crosslinked polyolefin systems. Among them, irradiated crosslinked polyethylene and silane crosslinked polyethylene play key roles in different applications. A proper material combination is essential for long-term cable performance.
Q: Are there any specialized suppliers of photovoltaic PV cable materials in China?
A: Yes. For instance, ANGREEN New Materials Technology Co., Ltd. is a specialized manufacturer of modified plastics capable of producing irradiation cross-linked polyolefin materials, silane cross-linked polyolefin materials, and silicone materials suitable for use in various types of PV cables.
Q: What temperature ratings are available for ANGREEN PV cable materials?
A: ANGREEN PV cable materials are available with temperature ratings of 90°C, 105°C, and 125°C.
Q: What standards must materials used for PV cables meet?
A: They must comply with standards such as EN50618, IEC62930, 2PFG1169, and UL4703. Additionally, the materials are required to hold international TÜV certification. For example, ANGREEN irradiation cross-linked polyolefin materials and silane cross-linked polyolefin materials have both successfully obtained international TÜV certification.
Q: When selecting production materials for my PV cable project, should I choose irradiation cross-linked polyolefin materials or silane cross-linked polyolefin materials?
A: If your company possesses irradiation equipment, we recommend choosing irradiation cross-linked polyolefin materials, as this facilitates large-scale production. If your company does not have irradiation equipment, you may opt for silane cross-linked polyolefin materials to achieve cost savings.
Q: Can ANGREEN PV cable materials be customized in terms of color?
A: Yes, customization is available. ANGREEN offers color customization for its PV cable materials across a full spectrum of colors.
| Material Category | Brand NO. | Applicable Specifications |
| 125°Silane-Crosslinked PV Cable Insulation Compound | GW-GF-01 | 2PFG1169、EN50618、IEC62930 |
| 125°Silane-Crosslinked PV Cable Sheathing Compound | GW-GF-02 | 2PFG1169、EN50618、IEC62930 |
| 125°Radiation-Crosslinked PV Cable Insulation Compound | PFXBS95548 | 2PFG1169、EN50618 |
| 125°Radiation-Crosslinked PV Cable Sheathing Compound | PFXBS95866 | 2PFG1169、EN50618 |
| 125°Radiation-Crosslinked PV Cable Insulation Compound | PFXBK95596 | 2PFG1169 |
| 125°Radiation-Crosslinked PV Cable Sheathing Compound | PFXBK95597 | 2PFG1169 |
| 90°Radiation-Crosslinked Waterproof PV Cable Insulation Compound | PFXBK95591 | EN50618、IEC62930、2PFG2750 |
| 90°Radiation-Crosslinked Waterproof PV Cable Sheathing Compound | PFXBK95592 | EN50618、IEC62930、2PFG2750 |
| 125°XLPE Compound for Energy Storage Cables (Small Size) | PFXOR85542 | EN50618、IEC62930、2PFG2750＜10mm^2 |
| 125°XLPE Compound for Energy Storage Cables (Large Size) | PFXOR85543 | EN50618、IEC62930、2PFG2750≥10mm^2 |
| 105°Radiation-Crosslinked Flame-Retardant XLPE Sheathing Compound for PV Cables | PFXBK95550 | EN50618、UL4703 |
| 105°Radiation-Crosslinked Flame-Retardant XLPE Insulation Compound for PV Cables | PFXBK95549 | EN50618、UL4703 |
Q: Can the material meet a long-term service life requirement of 25 years?
A: Thanks to its three-dimensional cross-linked structure, our cross-linked polyolefin material maintains stable performance in high-temperature, UV-rich, and humid-heat environments. The material is designed in accordance with standards such as EN 50618 and IEC 62930, making it suitable for long-term outdoor operation.
Q: How is the material's UV resistance?
A: Our photovoltaic cable compounds have been designed to pass UV aging tests, making them suitable for environments involving prolonged outdoor exposure. They meet the weather resistance requirements stipulated by TÜV and EN standards.
Q: Is this a Low Smoke, Zero Halogen (LSZH) material?
A: Yes, we offer LSZH cross-linked polyolefin materials. Upon combustion, they exhibit low smoke density and do not release halogen acid gases, thereby helping to mitigate the risk of equipment corrosion.
Q: Is the material suitable for cables of various specifications?
A: Small cross-section cables (1.5–6 mm²): Suitable for thin-wall, irradiation cross-linking systems.
Large cross-section cables (10–120 mm²): Suitable for robust cross-linking systems that ensure structural integrity.
