1.What is Solar cable？
Solar cables are used for power transmission. They are used on the DC side of solar power stations. They have great physical properties. These include resistance to high and low temperatures. Also, to UV radiation, water, salt spray, weak acids, and weak alkalis. They also have resistance to aging and flames.
Photovoltaic cables are also special Solar cables. They are mainly used in harsh climates. Common models include PV1-F and H1Z2Z2-K. Danyang Winpower is a solar cable manufacturer
Solar cables are often in sunlight. Solar energy systems are often in harsh conditions. They face high heat and UV radiation. In Europe, sunny days will cause the on-site temperature of solar energy systems to reach 100°C.
Photovoltaic cables are a composite cable installed on solar cell modules. It has an insulating covering and two forms. The forms are single-core and double-core. The wires are made of galvanized steel.
It can transport electrical energy in solar cell circuits. This allows cells to power systems.
2. Product materials:
1) Conductor: tinned copper wire
2) Outer material: XLPE (also known as: cross-linked polyethylene) is an insulating material.
3. Structure:
1) Generally pure copper or tinned copper core conductor is used
2) Inner insulation and outer insulation sheath are 2 types
4. Features:
1) Small size and light weight, energy-saving and environmental protection.
2) Good mechanical properties and chemical stability, large current-carrying capacity;
3) Smaller size, light weight and low cost than other similar cables;
4) It has: good rust resistance, high heat resistance, and acid and alkali resistance. It also has wear resistance and is not eroded by moisture. It can be used in corrosive environments. It has good anti-aging performance, and a long service life.
5) It is cheap. It can be used in sewage, rainwater, and UV rays. It can also be used in other strong corrosive media, such as acids and alkalis.
Photovoltaic cables have simple structure. They use irradiated polyolefin insulation. This material has excellent heat, cold, oil, and UV resistance. It can be used in harsh environmental conditions. At the same time, it has some tensile strength. It can meet the needs of solar power in the new era.
5. Advantages
The conductor resists corrosion. It’s made of tinned soft copper wire, which resists corrosion well.
The insulation is made of cold-resistant, low-smoke, halogen-free material. It can withstand -40℃ and has good cold resistance.
3) It resists high temperatures. The sheath is made of heat-resistant, low-smoke, halogen-free material. It can handle temperatures up to 120℃ and has excellent high-temperature resistance.
After irradiation, the cable’s insulation gains other properties. These include being anti-UV, oil resistant, and long lived.
6. Characteristics:
The cable’s characteristics come from its special insulation and sheath materials. We call them cross-linked PE. After irradiation by the accelerator, the cable material’s molecular structure will change. This will improve its performance in all ways.
The cable resists mechanical loads. During installation and maintenance, it can be routed on the sharp edge of the star top structure. The cable must withstand pressure, bending, tension, cross-tension loads, and strong impacts.
If the cable sheath is not strong enough, it will damage the cable insulation. This will shorten the cable’s life or cause problems like short circuits, fire, and injury.
7. Features:
Safety is a big advantage. The cables have good electromagnetic compatibility and high electrical strength. They can handle high voltage and high temperatures, and resist weather aging. Their insulation is stable and reliable. It ensures that AC levels are balanced between devices and meets safety requirements.
2) Photovoltaic cables are cost-effective at transmitting energy. They save more energy than PVC cables. They can detect system damage quickly and accurately. This improves system safety and stability and cuts maintenance costs.
3) Easy installation: PV cables have a smooth surface. They are easy to separate and plug in and out. They are flexible and simple to install. This makes it convenient for installers to work quickly. They can also be arranged and set up. This has greatly improved the space between devices and saved space.
4) The raw materials of photovoltaic cables follow environmental protection rules. They meet material indicators and their formulas. During use and installation, any released toxins and exhaust gases meet environmental rules.
8. Performance (electrical performance)
1) DC resistance: The DC resistance of the conductive core of the finished cable at 20°C is not greater than 5.09Ω/km.
2) The test is for water immersion voltage. The finished cable (20m) is put in (20±5)℃ water for 1h. Then, it is tested with a 5min voltage test (AC 6.5kV or DC 15kV) without breakdown.
The sample resists DC voltage for a long time. It is 5m long and in distilled water with 3% NaCl at (85±2)℃ for (240±2)h. Both ends are exposed to the water for 30cm.
A 0.9kV DC voltage is applied between the core and the water. The core conducts electricity. It’s connected to the positive pole. The water is connected to the negative pole.
After taking out the sample, they carry out a water immersion voltage test. The test voltage is AC
4) The insulation resistance of the finished cable at 20℃ is not less than 1014Ω·cm. At 90℃, it is not less than 1011Ω·cm.
5) The sheath has a surface resistance. It must be at least 109Ω.
9. Applications
Photovoltaic cables are often used in wind farms. They provide power and interfaces for photovoltaic and wind power devices.
2) Solar energy applications use photovoltaic cables. They connect solar cell modules, collect solar energy, and transmit power safely. They also improve power supply efficiency.
3) Power station applications: Photovoltaic cables can also connect power devices there. They collect generated power and keep power quality stable. They also cut power generation costs and boost power supply efficiency.
4) Photovoltaic cables have other uses. They connect solar trackers, inverters, panels, and lights. The technology simplifies cables. It is important in vertical design. This can save time and improve work.
10. Scope of use
It is used for solar power stations or solar facilities. It is for equipment wiring and connection. It has strong abilities and weather resistance. It is right for use in many power station environments worldwide.
As a cable for solar devices, it can be used outdoors in different weather. It can also work in dry and humid indoor spaces.
This product is for soft cables with one core. They are used on the CD side of solar systems. The systems have a max DC voltage of 1.8kV (core to core, non-grounded). This is as described in 2PfG 1169/08.2007.
This product is for use at Class II safety level. The cable can operate at up to 90℃. And, you can use multiple cables in parallel.
11. Main features
1) Can be used under direct sunlight
2) Applicable ambient temperature -40℃~+90℃
3) Service life should be more than 20 years
4) Except for 62930 IEC 133/134, other types of cables are made of flame-retardant polyolefin. They are low-smoke and halogen-free.
12. Types:
In the system of solar power stations, cables are divided into DC and AC cables. According to the different uses and use environments, they are classified as follows:
DC cables are mostly used for:
1) Series connection between components;
The connection is parallel. It is between strings and between strings and DC distribution boxes (combiner boxes).
3) Between DC distribution boxes and inverters.
AC cables are mostly used for:
1) Connection between inverters and step-up transformers;
2) Connection between step-up transformers and distribution devices;
3) Connection between distribution devices and power grids or users.
13. Advantages and Disadvantages
1) Advantages:
a. Reliable quality and good environmental protection;
b. Wide application range and high safety;
c. Easy to install and economical;
d. Low transmission power loss and small signal attenuation.
2) Disadvantages:
a. Certain requirements for environmental adaptability;
b. Relatively high cost and moderate price;
c. Short service life and general durability.
In short, photovoltaic cable is very useful. It is for transmitting, connecting, and controlling power systems. It is reliable, small, and cheap. Its power transmission is stable. It is easy to install and maintain. Its use is more effective and safe than PVC wire due to its environment and power transmission.
14. Precautions
Photovoltaic cables must not be laid overhead. They can be, if a metal layer is added.
Photovoltaic cables shall not be in water for a long time. They must also be kept out of humid places for work reasons.
3) Photovoltaic cables shall not be buried directly in the soil.
4) Use special photovoltaic connectors for photovoltaic cables. Professional electricians should install them.
15. Requirements:
Low-voltage DC transmission cables in solar systems have different requirements. They vary by the component’s use and technical needs. The factors to consider are cable insulation, heat resistance, and flame resistance. Also, high aging and wire diameter.
DC cables are mostly laid outdoors. They need to be proof against moisture, sun, cold, and UV. Therefore, DC cables in distributed photovoltaic systems use special cables. They have photovoltaic certification.
This type of connecting cable uses a double-layer insulation sheath. It has excellent resistance to UV, water, ozone, acid, and salt. It also has great all-weather ability and wear resistance.
Consider the DC connectors and the output current of PV panels. The commonly used PV DC cables are PV1-F1*4mm2, PV1-F1*6mm2, etc.
16. Selection:
The cables are used in the low-voltage DC part of the solar system. They have different requirements. This is because of differences in the use environments. Also, the technical needs for connecting different components. You need to consider a few factors. These are: cable insulation, heat resistance, flame resistance, aging, and wire diameter.
The specific requirements are as follows:
The cable between solar cell modules is generally directly connected. They use the cable attached to the module’s junction box. When the length is not enough, a special extension cable can be used.
The cable has three specifications. They are for modules of different power sizes. They have a cross-sectional area of 2.5m㎡, 4.0m㎡, and 6.0m㎡.
This cable type uses a double-layer insulation sheath. It resists ultraviolet rays, water, ozone, acid, and salt. It works well in all weather and is wear-resistant.
The cable connects the battery to the inverter. It requires multi-strand soft wires that have passed the UL test. The wires should be connected as close as possible. Choosing short and thick cables can cut system losses. It can also improve efficiency and reliability.
The cable connects the battery array to the controller or DC junction box. It must use a UL-tested, multi-strand soft wire. The wire’s cross-sectional area follows the array’s maximum output current.
The DC cable’s area is set based on these principles. These cables connect solar cell modules, batteries, and AC loads. Their rated current is 1.25 times their max working current. The cables go between solar arrays, battery groups, and inverters. The cable’s rated current is 1.5 times its max working current.
17. Selection of photovoltaic cables:
In most cases, the DC cables in photovoltaic power stations are for long-term outdoor use. Construction conditions limit the use of connectors. They are mostly used for cable connection. Cable conductor materials can be divided into copper core and aluminum core.
Copper core cables have more antioxidants than aluminum. They also last longer, are more stable, and have less voltage drop and power loss. In construction, copper cores are flexible. They allow for a small bend, so they are easy to turn and thread. Copper cores resist fatigue. They do not break easily after bending. So, wiring is convenient. At the same time, copper cores are strong and can withstand high tension. This makes construction easier and allows for machines to be used.
Aluminum core cables are different. They are prone to oxidation during installation due to aluminum’s chemical properties. This happens because of creep, a property of aluminum that can easily cause failures.
Therefore, aluminum core cables are cheaper. But, for safety and stable operation, use copper core cables in photovoltaic projects.
Post time: Jul-22-2024