China Zhenglan Cable Technology Co., Ltd Company News

18. What are the requirements for the mechanical strength of cable conductor connection points?   Answer: The mechanical strength of the connection point is generally lower than the tensile strength of the cable conductor itself. For fixedly laid power cables, the tensile strength of the connection point is required to be no less than 60% of the tensile strength of the conductor itself. 19. What are the main properties of the insulation layer material of power cables?   Answer: It should have the following main properties: (1) High breakdown strength; (2) Low dielectric loss; (3) Quite high insulation resistance; (4) Excellent discharge resistance; (5) Has certain softness and mechanical strength; (6) The insulation performance is long-term and stable. 20. The applications of wires and cables are mainly divided into three categories:   (1), power system The wire and cable products used in the power system mainly include overhead bare wires, busbars (busbars), power cables (plastic cables, oil-paper power cables (basically replaced by plastic power cables), rubber sheathed cables, overhead insulated cables), branch cables (replacing some busbars), electromagnetic wires, and electrical equipment wires and cables for power equipment, etc.   (2), Information transmission system The wires and cables used in information transmission systems mainly include local telephone cables, television cables, electronic cables, radio frequency cables, optical fiber cables, data cables, electromagnetic wires, power communication or other composite cables, etc.   (3), mechanical equipment, instrumentation systems In addition to overhead bare wires, almost all other products in this section are applied, but mainly power cables, electromagnetic wires, data cables, instrumentation cables, etc.   21. Wire and cable products are mainly divided into five categories:   (1), Bare wires and bare conductor products The main characteristics of this type of product are: pure conductor metal, without insulation and sheath layers, such as steel core aluminum stranded wire, copper aluminum busbar, electric locomotive wire, etc.; the processing technology is mainly pressure processing, such as smelting, rolling, drawing system, stranding/compression stranding, etc.; the products are mainly used in suburban areas, rural areas, user main lines, switch cabinets, etc.   (2), power cable The main features of this type of product are: extruding (winding) the insulation layer on the conductor, such as overhead insulated cables, or twisting several cores (corresponding to the phase line, neutral line and ground wire of the power system), such as overhead insulated cables with more than two cores , or add a sheath layer, such as plastic/rubber sheathed wire and cable. The main process technologies include drawing, stranding, insulation extrusion (wrapping), cabling, armoring, sheath extrusion, etc. There are certain differences in the different process combinations of various products. The products are mainly used in the transmission of strong electric energy in generation, distribution, transmission, transformation and power supply lines, with large currents (tens of tens of amps to thousands of amps) and high voltages (220V to 500kV and above).   (3) Wires and cables for electrical equipment The main features of this type of products are: a wide range of varieties and specifications, a wide range of applications, most of the operating voltages are 1kV and below, and new products are constantly derived for special occasions, such as fire-resistant cables, flame-retardant cables, low-smoke halogen-free/low-smoke Smoke-resistant low-halogen cables, termite-proof, mouse-proof cables, oil-resistant/cold-resistant/temperature-resistant/wear-resistant cables, medical/agricultural/mining cables, thin-walled wires, etc.   (4), communication cables and optical fibers (brief introduction) With the rapid development of the communications industry in the past two decades, products have also developed at an alarming rate. From the simple telephone and telegraph cables in the past, it has developed into thousands of pairs of voice cables, coaxial cables, optical cables, data cables, and even combined communication cables. The structural dimensions of such products are usually small and uniform, and require high manufacturing precision.   (5), electromagnetic wire (winding wire) Mainly used in various motors, instruments, etc. Derivatives/new products of wires and cables are mainly due to different application situations, application requirements, convenience of equipment, and reduction of equipment costs. They use new materials, special materials, or change the product structure, or improve process requirements, or will be different. A variety of products are produced by combining them. Use different materials such as flame-retardant cables, low-smoke halogen-free/low-smoke low-halogen cables, termite-proof, mouse-proof cables, oil-resistant/cold-resistant/temperature-resistant cables, etc.; change the product structure such as: fire-resistant cables, etc.; improve technology Requirements such as: medical cables, etc.; combined products such as: OPGW, etc.; convenient installation and reduced equipment costs, such as: prefabricated branch cables, etc.   22. What requirements should be met when laying cables? Answer: The following requirements should be met: (1) In terms of safe operation, try to avoid all kinds of external damage and improve the power supply reliability of cable lines; (2) Economically, consider the aspect of saving the most investment; (3) In terms of construction, the path of the cable line must be convenient for work and maintenance after operation.

11. What should be stated on the cable sign? What are the requirements for writing? Answer: The cable line design number, cable model, specification and starting point should be indicated on the signboard. Cables used in parallel should have sequence numbers. The handwriting is required to be clear and not easy to fall off.   12. How should the yellow wax silk ribbon, black glass paint ribbon, alkali-free glass ribbon, etc. used for making cable joints be dehumidified before construction? Answer: ① Constant temperature drying method: roll the insulating tape into a small roll with a diameter of 25~30mm, put it into a constant temperature drying oven at 110~120℃ for 4~5 hours, cool and dry, take it out, and put it into a dry sealed cylinder. ②Oil immersion moisture drainage method: Put the small roll of insulation tape into the cable oil with a constant temperature of 120~130℃, keep a distance of 30mm from the bottom of the pot. After a certain period of time, the oil surface will no longer produce foam, take it out, and put it into the stored cable. In oil barrels, the oil level should exceed all contained objects and be sealed. 13. What is the function of the cable outer sheath? Answer: Protect the inner protective layer from mechanical damage and chemical corrosion and enhance mechanical strength. 14. What requirements should outdoor cable trenches meet? Answer: The upper part of the cable trench should be slightly higher than the ground and covered with a concrete cover. The cables should be laid flat on the bracket and have good drainage pipes.   15. What is the function of the inner sheath of the cable? Answer: Keep the insulation layer from coming into contact with water, air or other objects, prevent the insulation from getting damp and prevent the insulation layer from mechanical damage.   16. What should you pay attention to when using wire cutters? Answer: Before use, be sure to check whether the insulation of the insulated handle is intact. Do not use wire cutters to cut metal wires exceeding the specifications allowed. It is also prohibited to use wire cutters instead of hammers to hit the tool to avoid damage.   17. What is insulation strength? Answer: When an insulating material is in an electric field, it will be broken down when the electric field intensity increases to a certain limit. This electric field intensity that leads to insulation breakdown is called insulation strength.

Armored cables are made of conductors of different materials installed in metal casings with insulating materials, and are processed into a flexible and solid assembly. The mechanical protective layer of armored cables can increase the mechanical strength of the cable and improve its corrosion resistance. It is a cable designed for areas prone to mechanical damage and erosion. It can be laid in any way, and is more suitable for direct burial in rocky areas. Armored cables are also divided into steel tape armored cables and steel wire armored cables.   1. Purpose: Steel tape armor is only used for the laying of directly buried cables or ordinary pipes, ordinary ground, tunnels, etc. The thin steel wire armor can withstand general longitudinal tension, so it is suitable for short-distance overhead laying or vertical and vertical laying. Abroad, there are more steel wire armored cables!   2. Price: The corresponding steel wire armor is more expensive. Because steel wire armor is difficult to produce and the cost is high.   3. Current-carrying capacity: There is not much difference, but they must use countermagnetic steel strips or steel wires.   4. Depending on the use environment, choose different forms of armored cables: steel tape armor can withstand mechanical pressure, and steel wire armor can withstand mechanical tension.   Zhenglan Cable can do both types of armored cable. Welcome your inquiry.

Dear Customer,   Thanks for your visiting our website.   Please be informed that our company will remain closed from September 29th to October 6th due to the National Day holidays Normal business will resume on October 7th. We apologize for any inconvenience caused by our temporary closure and appreciate your understanding.   Zhenglan Cable Technology Co., Ltd 2023.9.28

6. What regulations should be followed when selecting the cross-section of power cables? Answer: The selection of power cables should follow the following principles: (1) The rated voltage of the cable must be greater than or equal to the rated voltage of the power supply system at the installation point; (2) The continuous allowable current of the cable should be equal to or greater than the maximum continuous current of the power supply load; (3) The wire core cross-section must meet the stability requirements of the power supply system during short circuit; (4) Check whether the voltage drop meets the requirements based on the cable length; (5) The minimum short-circuit current at the end of the line should enable the protective device to operate reliably.   7. What are the advantages of cross-linked polyethylene cables and oil-paper cables? Answer: (1) Easy to install because it allows a small minimum bending radius and is lightweight; (2) Not affected by line differences; (3) Good thermal performance, allowing high operating temperature and large transmission capacity; (4) The cable accessories are simple and all are dry structures; (5) Operation and maintenance are simple and there is no oil leakage problem; (6) The price is lower; (7) High reliability and low failure rate; (8) Few manufacturing steps, simple process, and significant economic benefits.   8. What are the requirements for clamps for fixing AC single-core cables? Why? Answer: The clamp should have no iron parts to form a closed magnetic circuit. This is because when the cable core passes current, magnetic lines of force are generated around it. The magnetic lines of force are proportional to the current passing through the core. If magnetically conductive materials such as iron parts are used, according to It can be seen from electromagnetic induction that eddy currents will be generated in the iron parts to cause the cable to heat up and even burn the cable. Therefore, iron parts cannot be used as fixed fixtures for single-core AC cables.   9. What are the biggest features and advantages of heat shrinkable cable head accessories? Answer: The biggest feature of heat shrink accessories is that they use stress tubes instead of traditional stress cones. It not only simplifies the construction process, but also reduces the size of the joint terminals. It is easy to install, saves time and labor, has superior performance, and saves metal. Heat-shrinkable cable accessories are both potted and dry-packed, combining the advantages of both types of accessories.   10. What inspections should be carried out before laying cables? Answer: (1) The brackets should be complete and the paint should be complete. (2) The cable model, voltage, and specifications comply with the design. (3) The cable insulation is good. When there is doubt about the sealing of oil-paper cables, moisture judgment should be made; directly buried cables and small bottom cables should pass the DC withstand voltage test; oil samples of oil-filled cables should pass the test. (4) The oil pressure of oil-filled cables should not be lower than 1.47MPa.

1. What are the types of commonly used wires and cables according to their uses? Answer: According to the purpose, it can be divided into bare wires, insulated wires, heat-resistant wires, shielded wires, power cables, control cables, communication cables, radio frequency cables, etc. 2. What kinds of insulated wires are there? Answer: Common insulated wires are as follows: PVC insulated wire, PVC insulated flexible wire, nitrile polyvinyl chloride mixture insulated flexible wire, rubber insulated wire, agricultural underground direct buried aluminum core plastic insulated wire, rubber insulated cotton yarn Textile flexible wires, PVC insulated nylon sheathed wires, PVC insulated flexible wires for electricity and lighting, etc.   3. What are the cable accessories? Answer: Commonly used electrical accessories include cable terminal junction boxes, cable intermediate junction boxes, connecting pipes and terminals, steel plate junction slots, cable trays, etc.   4. What is the cable intermediate joint? Answer: The device that connects the conductor, insulation shielding layer and protective layer of the cable to the cable to connect the cable line is called the cable intermediate joint.   5. What aspects should be considered when selecting the cross section of the power cable? Answer: The following aspects should be considered: (1) The working current that the cable is allowed to pass through for a long time; (2) thermal stability in case of short circuit; (3) The voltage drop on the line cannot exceed the allowable working range.

Concentric Conductor Shielded Neutral Power Cable has advantages as below: 1. When the power is transmitted, it will not interfere with the surrounding electrical equipment; it also eliminates the impact of external electromagnetic interference on the electrical equipment connected to the cable. 2 It can avoid breakdown or damage caused by strong lightning electromagnetic effect voltage, and improve the lightning protection effect and reliability of high-rise buildings. 3. It can improve the sensitivity of the overcurrent protection device at the hand end of the line, so that the cable and the electrical equipment connected to it can be effectively protected. 4. It has low and uniform positive (reverse) sequence and zero sequence impedance, which is beneficial to improve the quality of copper electricity. 5. The grounding fault caused by one-phase insulation breakdown can be eliminated as soon as possible.

The International Energy Agency recently stated that by 2027, solar power generation is expected to surpass coal-fired power generation and become the main way of generating electricity. So, why is solar power likely to become the main force of new energy in the future? More than a decade ago, solar energy was insignificant in the global energy race, accounting for the smallest share of all major sources of electricity, less than 1%. But things have changed now, with the International Energy Agency (IEA) saying that within three years, solar will generate more electricity than natural gas. Within four years, by 2027, it could overtake coal as the dominant form of electricity generation. Solar electricity installation costs have dropped dramatically in recent years An important reason is that the installation cost of solar power has dropped significantly. Data show that for utility-scale solar energy, the average cost of construction and operation has continued to decline since 2009, and will only be about $36 per megawatt-hour by 2021, a drop of about 90% compared to 2009. The cost of coal has changed little, at about $108 per megawatt-hour in 2021. Bahar, an analyst for the International Energy Agency's renewable energy market, said that solar power is expected to account for almost 60% of new power installations in the next five years. Governments are increasingly paying attention to the development of renewable energy In addition, in recent years, governments of various countries have paid more and more attention to energy security, and have also introduced corresponding policies to support it. According to the EU plan, by 2025, its installed capacity of solar photovoltaic power generation will more than double that of 2020, reaching 320 GW, and by 2030 it will reach 600 GW. The U.S. Inflation Reduction Act is expected to allow solar developers to enjoy certain tax credits within 10 years to carry out long-term and large-scale construction.   Home solar power market has broad prospects Another point that cannot be ignored is that the construction scale of solar energy can be large or small. In addition to huge arrays, it can also be a single battery panel on the roof. Therefore, household solar power generation is also an important market. The CEO of a solar energy company in the United States mentioned in an interview with CNBC that the surge in demand for electric vehicles today may also drive the demand for household solar power generation in the future because it is convenient, cheap and reliable.  

Cable manufacturers are constantly challenged with wider temperature ranges, more shielding functions and higher mechanical durability, as well as characteristics such as bending resistance and chemical resistance required for extremely harsh environments and increasingly complex applications. However, cable failures and system downtime still occur from time to time, why?   Cable Faults Many problems caused by cable faults, especially those operating in extreme and harsh environments, can be avoided if the cables are selected correctly from the outset. People might say that choosing a cable is easy, but is that really the case? Indeed, matching the correct temperature range and relying on a PVC jacket for protection is simple. However, there are far more issues to consider.   Engineers have many details to consider before finalizing a perfectly matched cable. Flex and flex cables require specific flex shields. When the shield is torn and continuity is lost, the choice of standard foil shielding can lead to system failure. The distinction between flexibility and bendability should be kept in mind. It is important that the cables be able to be bent and fitted, the flexible cables are easier to install and also simplifies fault detection in cabinets and cable trays.   When the cable is used to connect to the cabinet, the round cable provides a better seal than the typical spiral cable. Therefore, it is necessary to correctly select the degree of bending after considering the line. In some manufacturing applications, cables will be constantly being bent. Ability to withstand millions of bends is more complicated than flexibility. So, how to choose a curved cable? The first thing to consider is the type of bending, is it uniaxial, twisted, or multi-axial? Each type requires different characteristics of the cable.

Dear Sir/Madame, Email received. Kindly note that we are now spending a 3-day Dragon Boat holiday from June 22nd(Thirsday) to June 24th(Saturday). During holiday we have limit access to email, we're sorry for not being able to reply you or give you quotation timely. Once we come back, we will contact you at our first time. Thanks for your kind understanding. ---------------------------------- Estimado Señor / Señora, Correo electrónico recibido. Tenga en cuenta que ahora estamos pasando unas vacaciones de 3 días en Dragon Boat del 22 de junio (jueves) al 24 de junio (sábado). Durante las vacaciones, tenemos acceso limitado al correo electrónico, lamentamos no poder responderle o darle una cotización a tiempo. Una vez que volvamos, nos pondremos en contacto con usted en nuestra primera vez. Gracias por su comprensión. Zhenglan Cable Technology Co., Ltd 2023/6/21