China Zhenglan Cable Technology Co., Ltd Company News

During the construction of a solar photovoltaic power station, in addition to the main equipment, such as photovoltaic modules, inverters, and step-up transformers, the photovoltaic cable materials connected to the photovoltaic power station have the same effect on the overall profitability, operation safety, and high efficiency of the photovoltaic power station. plays a vital role.. According to the system of solar photovoltaic power station, cables can be divided into DC cables and AC cables. According to the different uses and use environments, they are classified as follows: 1. DC cable (1) Serial cables between components. (2) Parallel cables between the strings and between the strings and the DC distribution box (combiner box). (3) The cable between the DC distribution box and the inverter. The above cables are all DC cables, and there are many outdoor layings. They need to be moisture-proof, sun-proof, cold-resistant, heat-resistant, and UV-resistant. In some special environments, they also need to be protected from chemicals such as acid and alkali. 2. AC cable (1) The connecting cable from the inverter to the step-up transformer. (2) The connecting cable from the step-up transformer to the power distribution device. (3) The connecting cable from the power distribution device to the power grid or the user. This part of the cable is an AC load cable, which is laid in the indoor environment and can be selected according to the general power cable selection requirements. 3. Photovoltaic special cable A large number of DC cables in photovoltaic power plants need to be laid outdoors, and the environmental conditions are harsh. The cable materials should be determined according to the resistance to ultraviolet rays, ozone, severe temperature changes and chemical erosion. The long-term use of ordinary material cables in this environment will cause the cable sheath to be fragile, and even decompose the cable insulation. These conditions will directly damage the cable system, but also increase the risk of short-circuiting the cable. In the medium and long term, the possibility of fire or personal injury is also higher, which greatly affects the service life of the system. 4. Cable conductor material Most of the DC cables used in photovoltaic power plants work outdoors for a long time. Due to the limitation of construction conditions, connectors are mostly used for cable connection. Cable conductor materials can be divided into copper core and aluminum core. 5. Cable insulation sheath material During the installation, operation and maintenance of photovoltaic power plants, cables may be routed in the soil below the ground, in overgrown rocks, on the sharp edges of roof structures, or exposed to the air, and the cables may be impacted by various external forces. If the cable jacket is not strong enough, the cable insulation will be damaged, affecting the service life of the entire cable, or causing problems such as short circuits, fire and personal injury hazards.

Dear All, Wish you a happy International Workers' Day. Hope all of your efforts will be rewarded and all of your hard work will have gains. China's legal holiday for this will be from April 30th(Saturday) till May 4th(Wednesday). Work resume from May 5th( Thirsday). During holiday, we may have limited access to email, so shall any delays of response. Kindly ask for your understanding. Zhenglan Cable Technology Co., Ltd April 30th, 2022  

Power cables are one of the indispensable materials for power transmission and are widely used in economic production. Once a cable fails, it will not only threaten the safe and stable operation of the power grid, but also cause significant economic losses to families and society. Now there are many unqualified cables in the market that are confusing consumers' choices with fake and shoddy cables. The following will introduce the identification method of inferior cables. 1. Unqualified wires and cables   Marking is the main way to identify the basic information of products using wires and cables. According to the standard, the main contents of the mark are: product model, specification, standard, manufacturer, origin, etc. within a certain marking distance. When the mark is unqualified, it will cause Construction personnel identify errors, and in severe cases, construction personnel identify faults that can lead to electrical accidents.  

The rapid development of electric power industry has promoted the development of the electrical industry supporting the electric power industry, especially the wire and cable industry. The variety development of wire and cable shows a diversified trend. Wires and cables have developed from simple power transmission to multi-function, that is, some new characteristics have been added according to different uses, such as the water resistance requirements of power cables. With the deepening of the research and understanding of insulation water absorption and water tree, people are more and more aware of the importance of waterproof performance for medium and high voltage power cables. In areas with high groundwater level or perennial rainfall. More and more users require waterproof performance for cables.   After water is immersed in the cable, the main influence is on the conductor and insulation of the cable. As far as the conductor is concerned, the cable is in a thermal stable state during normal operation, and the conductor temperature is generally above 60. If there is water immersion, it will lead to conductor oxidation and increase the energy loss resistance between conductor single wires, which increases the conductor resistance and the energy loss of transmission line, In terms of insulation, although polyethylene is a non-polar hydrophobic material that is very difficult to dissolve in water, polyethylene is a semi crystalline polymer composed of crystalline phase and amorphous phase. The phase structure of polyethylene is compact, but there are defects at the grain boundary; The molecular arrangement in the amorphous phase is loose. There is a large gap between molecules. Water molecules are polar. Under the combined action of diffusion force and electric field force under alternating electric field, water molecules can easily penetrate into the capacity gap of amorphous phase and grain boundary defects of crystalline phase of polyethylene. The above problems also exist in the molecular structure of cross-linked polyethylene. At the same time, there are many cross-linked by-products in cross-linked polyethylene as impurities, so cross-linked polyethylene also has large water absorption under alternating electric field. Cross linked polyethylene and polyethylene insulation will produce water tree after absorbing water, which will cause breakdown and damage to the running cable.   Zhenglan Cable Technology Co., can do radinal water prevention structure by adding water prevention tape into different layer of the MV cable. If you are looking for such performance for MV cable, please come to us.

Dear Customer, Here comes China's Traditional Qingming Festival, a festival for worshiping ancestors, mourning passed-away relatives, spring outings. We will be on holiday from Sunday(April 3rd) to Tuesday(April 5th). Work resume on Wednesday(April 6th). During holiday, we may have limit access to email. Shall any delays of response, kindly ask for your understanding. Regards Zhenglan Cable Technology Co., Ltd. April 2nd, 2022

Shielded control cable is generally used as the connecting line of electrical instruments, which is suitable for the connecting line of electrical instruments with AC rated voltage of 450 / 750V and below and the transmission line of automatic control system. It has excellent properties such as oil resistance, waterproof, wear resistance, acid and alkali resistance, various corrosive gases, aging resistance and non combustion. Shielded control cable is a cable with a layer of mesh copper wire or metal wire braided around one or more wires. This layer of mesh wire can prevent lightning stroke, and external signals can not interfere with its. The shielding layer can also play a certain role in leakage protection. If the cable is damaged and electric leakage occurs during use, the shielding layer can lead the leaked current to the grounding wire, which plays a certain role in safety protection. At the same time, it can also protect the cable conductor. The function of shielding layer and grounding wire of shielding control cable is: the shielding layer is divided into internal shielding and external shielding. They are all designed to make good contact between the cable conductor and the insulating layer, and between the cable insulating layer and the inner protective layer, so as to eliminate the increase of surface electric field intensity caused by the unsmooth surface of the conductor and the inner protective layer Service characteristics of shielded control cable: (1) Allowable bending radius of cable: the minimum bending radius of non armored cable is 6 times of the outer diameter of the cable. Fluoroplastic insulated and sheathed cables shall be at least 8 times of the outer diameter of the cable. Copper tape shielded or steel tape armored cable shall be at least 12 times of the outer diameter of the cable. (2) Maximum working temperature: the insulation of polyperfluoroethylene propylene (F46) shall not exceed 200 ℃. Soluble polytetrafluoroethylene (PFA) insulation shall not exceed 260 ℃. (3) Minimum ambient temperature: PVC sheath: fixed laying - 40 ℃, non fixed laying - 15 ℃. Fluoroplastic and silicone rubber sheath: fixed laying - 60 ℃, non fixed laying - 20 ℃. The cable installation and laying temperature shall not be lower than 0 ℃ (fluoroplastic, silicone rubber and nitrile sheathed cable shall not be lower than - 25 ℃).

1. Low-smoke halogen-free wire refers to the environmentally friendly wire that does not contain halogen, lead, cadmium, chromium, mercury and other environmental substances. It will not emit toxic fumes when burning, and will not produce secondary hazards. It meets the requirements of modern fire safety. ..   2. The maximum rated temperature can reach 90℃ during long-term operation, and the maximum temperature of the wire conductor can reach 250℃ during short circuit (the longest duration does not exceed 5S), and the current carrying capacity is greater than that of PVC insulated wires.   3. The outer diameter of this kind of wire is smaller than the outer diameter of the full PVC insulated wire of the same specification and cross-section. In the construction of the pipe, the diameter of the pipe can be reduced, or more wires can be passed under the condition of the same pipe diameter, so as to reduce the construction and installation cost. .

Low-smoke halogen-free flame-retardant cables have flame-retardant properties, and the ignition delay is only limited to a certain range. It also has low smoke and harmlessness, little smoke when burning, and no corrosive gas escapes.   In addition to transmitting power under normal working conditions, the low-smoke halogen-free fire-resistant cable can still maintain normal operation for a certain period of time when it is on fire. Building fire protection system, emergency lighting system, life-saving system, alarm and important monitoring circuit, etc.

This question is wrong, and aluminum also rusts, but when aluminum rusts, it does not rust like iron until it is completely rusted. ​​  The oxidation of metal by oxygen in the air is rust. Aluminum reacts chemically with oxygen to form aluminum oxide, which is aluminum rust. Aluminum rust is very thin, its thickness is only ten thousandths of a millimeter, but it is very hard and very wear-resistant. It clings to the surface of the aluminum so that the aluminum inside is not exposed to the outside air, preventing the aluminum from continuing to rust.

1. Low resistivity: the resistivity of aluminum core cable is about 1.68 times higher than that of copper core cable.   2. Good ductility: the ductility of copper alloy is 20 ~ 40%, that of electrical copper is more than 30%, and that of aluminum alloy is only 18%.   3. High strength: the allowable stress of copper is 7 ~ 28% higher than that of aluminum at room temperature. Especially the stress at high temperature, the difference between the two is very far.   4. Fatigue resistance: aluminum is easy to break after repeated bending, while copper is not. In terms of elasticity index, copper is also about 1.7 ~ 1.8 times higher than aluminum. (low voltage power cable, medinum voltage power cable)   5. Good stability and corrosion resistance: copper core is resistant to oxidation and corrosion, while aluminum core is vulnerable to oxidation and corrosion.   6. Large current carrying capacity: due to low resistivity, the allowable current carrying capacity (maximum current that can be passed) of copper core cable with the same section is about 30% higher than that of aluminum core cable   7. Low voltage loss: due to the low resistivity of copper core cable, when the same current flows through the same section. The voltage drop of copper core cable is small. The same transmission distance can ensure high voltage quality; Under the condition of allowable voltage drop, the transmission of copper core cable can reach a long distance, that is, the power supply coverage area is large, which is conducive to network planning and reduce the number of power supply points.   8. Low heating temperature: under the same current, the heating capacity of copper core cable with the same section is much smaller than that of aluminum core cable, making the operation safer. (Aluminum conductor steel reinforced, ACSR)   9. Low energy consumption: due to the low resistivity of copper, compared with aluminum cable, the power loss of copper cable is low, which is obvious. This is conducive to improving the utilization rate of power generation and protecting the environment.   10. Oxidation resistance and corrosion resistance: the connector of copper core cable has stable performance and will not cause accidents due to oxidation. The joint of aluminum core cable is unstable, and accidents often occur due to the increase of contact resistance and heating due to oxidation. Therefore, the accident rate is much higher than that of copper core cable.   11. Convenient construction: The copper core has good flexibility and small allowable bending radius, so it is convenient to turn and pass through the pipe; The copper core is anti fatigue and not easy to break after repeated bending, so the wiring is convenient; The copper core has high mechanical strength and can bear large mechanical tension, which not only brings great convenience to the construction and laying, but also creates conditions for mechanized construction. (overhead insulated cable, electrical control cable)