How much do you know about the difference between RV and BVR

Both BVR and RV are indispensable decoration wires in the decoration industry. They have good flexibility, high conductivity, abrasion resistance, aging resistance, and very reliable safety and reliability. They are also multi-strand flexible wires commonly used in the market. . So, what is the difference between these two kinds of wires? What are the similarities?
Similarities between the two
1. Both are copper core PVC insulated flexible wires, which are composed of multiple strands of thin copper wires twisted together;
2. The structure of the product is all composed of conductor and PVC insulation layer
3. All copper core conductors are single core
4. In terms of colors, both have multiple colors-red, yellow, black, blue, etc.

The difference between BVR and RV
1. The executive standards of the two are different: the executive standard of BVR wire is GB/T 5023.3-2008, and the executive standard of RV wire is GB/T 3956 category 5;
2. The voltage levels of the two are different: the rated voltage of BVR is 450/750V, and the rated voltage of RV is 300/300V;
3. Purpose: BVR is mostly used for wiring wires. It is used in soft occasions. In many cases, it can be used instead of BV wire. RV wire is mostly used as the internal connection wire of various electrical equipment. Security equipment and instrumentation are also often used. It is used, so the RV line is softer, so it is called “electronic line”.

Wire specifications
4. The diameter of the core is different: the diameter of the copper wire that composes the conductor is different for the wire of the same specification; for example, the wire of the same 2.5mm2, BVR is made of 19 thin copper wires of 0.41mm twisted together, and RV is made of 49 A 0.25mm thin copper wire is twisted together.
5. Temperature: The maximum working temperature of conventional BVR wire is 70°C, and that of RV wire is 80°C. Of course, if you have special requirements, you can choose the high temperature resistant type.

Photovoltaic cable: PV1-F1

Photovoltaic cable: PV1-F1*4mm2
The cable from the string to the combiner box is generally used: photovoltaic cable PV1-F1*4mm2.
Features: The photovoltaic cable has a simple structure. The polyolefin insulation material used in it has excellent heat resistance, cold resistance, oil resistance, and ultraviolet resistance. It can be used under harsh environmental conditions and has a certain mechanical strength.
Laying: It can be protected by passing through the pipe, and the component bracket is used as the channel and fixing for cable laying to reduce the impact of environmental factors.

Power cable: ZRC-YJV22
Steel tape armored flame-retardant cross-linked cable ZRC-YJV22 is widely used in: combiner box to DC cabinet, DC cabinet to inverter, inverter to transformer, transformer to power distribution device, power distribution device to the power grid connecting cables.

The nominal cross-sections of ZRC-YJV22 cables commonly used in photovoltaic power generation systems are: 2.5mm2, 4mm2, 6mm2, 10mm2, 16mm2, 25mm2, 35mm2, 50mm2, 70mm2, 95mm2, 120mm2, 150mm2, 185mm2, 240mm2, 300mm2.


(1) The texture is hard, the temperature resistance grade is 90°C, it is easy to use, has the characteristics of low dielectric loss, chemical corrosion resistance and no drop limit for laying.
(2) It has high mechanical strength, good environmental stress resistance, good thermal aging performance and electrical performance.

Laying: It can be buried directly, suitable for fixed laying, and adapt to the needs of different laying environments (underground, water, trench pipes and tunnels)

The selection of cable path should meet the following requirements

(1) Avoid the cable from being exposed to mechanical external force, overheating, corrosion and other hazards.
(2) Make the cable shorter when meeting safety requirements.
(3) Easy to install and maintain.
(4) Avoid places that will be excavated
(5) The cable should meet the requirements of the allowable bending radius of the cable in any way of laying and all path conditions of the cable.

Environmental cables will become the global cable development trend?

In the new century, the importance of the ecological environment has become increasingly prominent, and environmental protection has gradually become the focus of attention and the mainstream of international development. Countries, organizations, companies and individuals all over the world are actively seeking environmental protection methods, and the laws and regulations that are compatible with them are becoming more complete and specific. Wires and cables are special commodities related to people’s life safety and the normal operation of almost all industries. In the face of people’s growing concern about the living environment and living environment, the market prospects of environmentally friendly cables are also increasingly promising, and gradually become the development trend of global power cables .The development potential cannot be underestimated.

Environmentally friendly cables refer to no heavy metals such as lead, cadmium, hexavalent chromium, mercury, etc., and no bromine-based flame retardants. They have been tested by SGS recognized testing organizations for environmental performance, and comply with the European Union Environmental Protection Directive (RoSH) and exceed its index requirements . It does not produce harmful halogen gas, does not produce corrosive gas, generates less fever when burned, and does not pollute the soil.


With the formulation of the European Union’s environmental protection directives, Europe, the United States, Japan and other countries have increasingly higher environmental protection requirements for the cables used. They have banned the use or import of non-environmental-friendly cables. The international market’s demand for environmentally-friendly cables is advancing with each passing day. With the maturity of environmentally-friendly cable production technology, the research and development and large-scale adoption of eco-friendly wires and cables has become an international trend.

Although the pace of China’s environmental protection cables lags behind foreign countries, it still conforms to the green trend and is constantly developing and improving the environmental protection cable market. The development and production of domestic environmental protection cables have also attracted attention from all parties. At the annual meeting of the national wire and cable industry, a green environmental protection — sustainable development strategy was formally proposed. It also clearly stipulates that “civil buildings with a height of more than 100 meters must use low-smoke, halogen-free, Class A flame-retardant wires and cables. High-rise buildings with a height of more than 100 meters and civil buildings less than 100 meters, such as a certain scale Hospitals, public entertainment venues, underground shopping malls, libraries, stations, supermarkets, terminal buildings, office buildings…, at least smoke-free, low-halogen and flame-retardant cables should be used.” One of the key projects of Zhejiang Province’s block industry standardization in 2012 ——The successful acceptance of the environmental protection wire and cable alliance standard marks a big step forward in the formulation of environmental protection standards in China.

It can be seen that the ecological environment-friendly cable market has a very broad prospect, which will undoubtedly bring new space and opportunities to the sustainable development of the wire and cable industry.

In many places in key projects, low-smoke and halogen-free wires and cables are used in places such as fire fighting, monitoring, and alarms. People usually call them environmentally friendly cables. In fact, environmentally friendly cables do not refer to low-smoke, halogen-free wires and cables. It is a cable produced in accordance with the Japanese FN cable manufacturing standard.

With the global promotion and spread of the concept of green environmental protection, the concept of environmental protection is gradually permeating all walks of life, and with the gradual use of environmentally friendly products and gaining popularity, the wire and cable industry has also begun to attach importance to the development and promotion of environmentally friendly cables. Our country also attaches great importance to this field, and relevant laws and regulations expressly require that in the construction of major projects, the use of non-environmental protection cables is strictly prohibited.

So what is an environmentally friendly cable, and what are its characteristics?

1. High flame Retardancy: The environmental protection cable can fully guarantee its high building requirements for fire protection. In the event of a fire, the environmental protection cable can not only be difficult to burn, but also prevent the spread of flames and the expansion of disasters after burning.

2. Halogen-free: The use of green environmental protection insulation layer, sheath an special oxygen barrier materials not only make the environmental protection cable have good electrical and physical and mechanical properties, but also ensure that the product is halogen-free and solve the problem of burning “Secondary pollution” avoids carcinogenic “dioxin” substances produced when traditional PVC cables burn.

3.metals harmful to the human body. When the environmental protection cable is used and disposed of, it will not pollute the soil and water sources. And after harsh toxicity experiments, the white rats were safe and sound under the specified experimental conditions.3. Low toxin: The insulation and sheath of cable do not contain lead, cadmium and other heavy

4. No corrosive gas: new special coating materials that do not pollute the environment are used, so that environmentally friendly cables will not produce toxic gases such as HCL during production, use and combustion, and emit very little acid gas, which is harmful to personnel, equipment and instruments. Less damage and more environmentally friendly features.

5. High light transmittance: The smoke produced when the environmental protection cable burns is extremely thin, which is conducive to the evacuation of personnel and the conduct of firefighting. Generally speaking, the light transmittance of environmentally friendly cable products is greater than 40%, which is far higher than the standard of less than 20% for traditional flame-retardant cables and cables.

6. High protection against ultraviolet rays or water: This performance can make the environmental protection cable less likely to be weathered during use, slow down the aging speed of the environmental protection cable to a certain extent, and extend its service life.

In general, environmentally friendly cables are a major trend. In recent years, the sales share of environmentally friendly cable products has increased dramatically. Because environmentally friendly cables have the characteristics of non-toxic and non-polluting to people and the environment, high safety and reliability, and long service life, they are expected to become the mainstream of the future cable market.

Discussion on environmental protection requirements of PVC cables and wires

The use of non environmental protection cables is strictly prohibited in developed countries, and China also attaches great importance to this field. China’s relevant laws and regulations clearly require the use of PVC wires and cables in important buildings. Halogen free and low smoke crosslinked PVC wires and cables must be used to avoid heavy smoke and chlorine gas causing casualties in case of fire.

Environmental protection cable will effectively drive the development of cable industry, enhance the competitiveness of cable manufacturer, and make the cable industry more and more stable on the road of sustainable development in green practice and innovation. In recent years, China’s cable enterprises have gradually made efforts to environmental protection cables and low smoke and halogen-free cables. As far as possible, they do not contain heavy metals such as lead, cadmium, mercury, bromine flame retardants, harmful halogen gases, corrosive gases, less heat during combustion, and no soil pollution. Environmental protection cables will be more favored by the market, and will be recruited by power grid companies It is easier to get high order in the bid.

The user’s requirements for environment-friendly wires and cables can be summarized as follows:

1. Low content of lead and heavy metals is required

It is well known that lead and some heavy metals will have adverse effects on human health. In PVC formulation, additives such as lead, cadmium, barium and other heavy metal compounds are usually needed. However, since the 1990s, some developed countries and large electric companies have successively formulated laws and regulations. In the PVC wires and cables used, there are eight kinds of heavy metal content shall not be greater than the regulations. These new regulations not only bring new business opportunities to wire and cable manufacturers, but also bring serious challenges to PVC cable manufacturer.

2. Low smoke and low hydrogen oxide are required

Good flame retardant performance is a very obvious advantage of PVC wire and cable. However, when ordinary flame retardant PVC cable is on fire, it will release thick black smoke and a large amount of HCI gas, which will cause “secondary disaster” after the fire, and seriously affect personnel evacuation and fire rescue work. Therefore, in addition to the flame retardant requirements for wires and cables, the requirements of “low smoke” and “low HCI” will be put forward in some applications.

3. Low toxicity or non toxicity is required

In addition to lead-free and heavy metal free, non-toxic (or low-toxic) cables are required for some household appliances, medical and health appliances and children’s electric toys that may come into contact with food and blood products. This means that all constituent materials used in PVC formulations should be non-toxic. There are a lot of plasticizers in cable materials, but the non-toxic plasticizers must be used to manufacture non-toxic materials. Therefore, the requirements of this PVC material are higher than that of lead-free and heavy metal free materials, and the price is naturally more expensive.

4. Other prohibited items

At present, the regulations being reviewed by the EU impose restrictions on the following items to ensure that wires and cables meet the requirements of environmental protection. For example: 1) asbestos; 2) biphenyl and its ethers, polybrominated phenol; 3) polychlorinated biphenyls; 4) short chain (C10-C13) chlorinated paraffin.

With more and more attention to environmental issues, many countries have formulated a variety of environmental protection policies, so people prefer to use green cable. Low smoke halogen-free flame retardant cable material is one of the most popular environmental protection cables. Although China’s market demand for green cable is growing, compared with developed countries, China still has a long way to go in terms of relevant policy formulation and mandatory application. China should improve the environmental protection cable standards as soon as possible.

Treatment method of PVC power cable affected by damp

Cables, especially PVC insulated power cables, have been widely used in urban power grid reconstruction projects. However, due to the particularity of the cable, the installation, operation and maintenance of the cable have special requirements. Cable insulation resistance is reduced by damp or water intrusion, which is an important aspect of cable line operation accidents.

Cause and harm of cable damp and water inflow

PVC power cable affected by damp  (1) When the new cable is delivered from the factory, both ends of the cable are sealed with plastic sealing sleeve. However, after a section of cable is used at the construction site according to the actual situation, the remaining part is simply wrapped with plastic cloth. As it is usually placed in the open air and the sealing is not good, water vapor will inevitably seep into the cable after a long time.

(2) During power cable laying, it is necessary to often cross roads, bridges and culverts. Due to weather or other reasons, a lot of water is accumulated in the cable trench. During the laying process, it is inevitable that the cable head will be immersed in the water, and the water will enter the cable due to loose wrapping or damage of plastic cloth. In addition, the outer sheath and even steel armor will sometimes occur during traction and pipe threading Scrape phenomenon, when using mechanical traction, this phenomenon is particularly prominent.

(3) After the completion of cable laying, due to the limitation of site construction conditions, the cable head can not be made in time, so that the cable fracture without sealing treatment is exposed to the air for a long time, even immersed in water, so that a large amount of water vapor enters the cable.

(4) During the manufacturing process of cable head (including terminal head and intermediate joint), due to the negligence of construction personnel, the newly treated cable end sometimes falls into the water on site.

(5) In the normal operation of the cable, if the breakdown and other faults occur for some reason, the water in the cable trench will enter the cable along the fault point; in the civil construction, especially in the construction site using large construction machinery, the cable damage or breakdown accidents caused by various human factors are also common. When this kind of accident occurs, the cable insulation will be seriously damaged, which will also cause cable water intrusion.


After the cable enters water, the aging phenomenon will occur under the action of electric field, which will eventually lead to cable breakdown.