Long-term cooperation between Yutong New Energy Vehicle and Wanda Aluminum

Yutong aluminium checker plate

It was learned from Zhengzhou Yutong Bus Co., Ltd. that the “2021 Annual Social Responsibility Report” released by the company shows that Yutong will achieve operating income of 25.7 billion yuan in 2021, an increase of 15.9%, and pay taxes of more than 1.3 billion yuan, achieving performance for 18 consecutive years. Continued growth.
According to the “Report”, in 2014 Yutong continued to lead the bus industry, with its bus sales exceeding 60,000 units, becoming the world’s largest bus sales company.

The aluminum alloy plate produced by Henan Wanda Aluminum has always been favored by Yutong Bus Company, especially the Aluminium checker plate, aluminum plate and other products, which have always been the most ideal materials in the new energy vehicle industry.

Yutong aluminium checker plate

The rapid growth of the new energy bus market has become an important factor driving the changes in Yutong’s business revenue. In 2021, Yutong Bus will sell a total of 7,405 new energy buses. Up to now, it has promoted a total of 13,798 new energy buses, becoming the first new energy bus in the world. A company with over 10,000 sales. It is equivalent to reducing carbon dioxide emissions by more than 464,000 tons per year, equivalent to the carbon dioxide absorption of 1,272 hectares of broad-leaved forest in one year. And Wanda Aluminum also wants Yutong Bus to provide a good product manufacturing plan.

In 2021, Yutong’s goal is to strive to achieve an operating income of 27.7 billion yuan, continue to maintain its advantages in passenger car sales, and focus on the new energy passenger car market. It is reported that in 2022, Yutong invested 3.86 billion yuan to build a new energy-saving and new energy bus industrialization base that has been officially put into production, with an annual production capacity of 30,000 vehicles, which will further reflect its economic benefits in 2015. The new energy bus technology is still in the early stage of development, and the speed of technological upgrading is very fast. Whether the new energy bus technology can make further breakthroughs will be the key problem to be solved by Yutong in the next stage.

Precautions for insulation high voltage test

Work on electrical equipment, except for a small number of people who are charged during the operation of the equipment, generally must be carried out under the state of equipment power outage. Pilot holdings are also required for power outage equipment, such as electricity inspection, grounding wire and other technologies to ensure personal safety. measure. Conduct electrical tests on power-off electrical equipment, especially high-voltage electrical tests. In addition to cutting off all possible power sources of the equipment, the test power supply must also be used to pressurize the equipment under test so that the equipment generates high voltage to achieve the purpose of the test. . Because the wiring of the tested equipment must be frequently disconnected before and after the pressure; the equipment with larger capacitance or the equipment under test with electrostatic induction must be discharged or grounded after the test; the pressure of the tested equipment is generally several times higher than the operating voltage , And the test auxiliary power cables are mostly exposed to prevent high-voltage electric shock accidents during the test, and to ensure the safety of testers and related workers. The following main safety precautions should be observed for high-voltage electrical test work:
1. The test personnel must be competent for the work, and the test personnel shall not be less than two, and there shall be a person in charge of the test to formulate and implement safety measures.
High-voltage test personnel must be clear about the test purpose, method (including familiarity with the performance of the test instrument, use method, etc.) and safety measures to be taken. Before work, the person in charge shall arrange the safety precautions of the test work in detail by all test personnel. The live test shall formulate safety measures according to the site conditions. Important special tests, research tests and tests in the operating system must have test plans and It can be carried out only after the approval of the relevant leaders. In this way, the test work can be carried out safely under the conditions of organization, leadership, safety measures, and people at all levels. Failure to do so, especially if safety measures are not implemented, will lead to accidents.


For example, when a technician in the electrical laboratory of a power supply station is doing the dielectric loss angle test of the switch, he mixes the test wiring in use with the unused wire, and also pressurizes and cleans it, so that the touch has been pressurized to 3,000 On the tip of the volt wire, he was electrocuted.
2. Pilot holdings explained in detail to clarify the scope of work, to clearly separate the tested equipment from other equipment, and to monitor the equipment for high-voltage electrical test work when the equipment was powered off. The work ticket system should be implemented, and the work permit procedures should be performed with the operating personnel to clarify The scope of power outage work, and in accordance with the provisions of the electrical parts of power plants and substations in the “Electrical Safety Work Regulations”, fences or fences shall be installed at the test site, and the signboard of “Stop! High Voltage Danger” shall be hung on the fences and monitored by someone. . When the two ends of the tested device are not in the same place, the other end should also be guarded. The purpose is to avoid misunderstanding the scope of power outages. However, in the accidents that occurred, some did not set up barriers or fences, did not set up guardians, and some were at the end of the fence played a role. An example is as follows: A high-voltage test group in a substation conducts a 35 kV 312 switching medium loss angle test. Since the work fence cannot distinguish between power outages and live equipment, a tester was unsupervised when he stepped off the switch and then switched on again. Without clarifying the equipment under test, he accidentally boarded the 312 switch that was in operation, and died of electrocution.
3. Explain in detail, adhere to the system of rechecking the wiring before the test
In the test work, the wiring is disconnected frequently, and the system of rechecking the wiring before the test is carefully implemented to correct the wrong wiring in advance and avoid accidents due to the wrong wiring. Therefore, rechecking the connection before the test is a basic system for test work, and it is also an effective measure to prevent electric shock accidents during test work and ensure personal safety. This system requires careful implementation and persistence. It should be treated to lower-level workers. , The connection re-examination of trainees should be focused, and senior workers or simple connection cannot be relaxed, otherwise the purpose of re-examination and connection cannot be achieved.
For example, a power plant uses a 100-kV high-pressure test machine in a high-voltage test room to perform a pressure test of a 6-kV porcelain bottle. Before the test, the connection line of the booster was not checked in detail, and the connection of the porcelain bottle under test was connected. When the pressure reached 42 kV, it was discovered that there was a plastic wire connected to the porcelain bottle at the high voltage outlet of the booster, which reached 110 thousand. In the substation, about 50 meters, the test was immediately stopped and the line was dismantled. This line was originally left after the 110 kV switch was tested more than ten days ago, and it was tied to the substation structure. There were more than ten construction workers working near the structure. Fortunately, these workers were not close when the pressure was applied. Or touch the wire.
4. During the test work, you should stand on an insulating mat or wear insulating shoes. This is a safety measure to prevent electric shock accidents or reduce the degree of injury


For example, when a test worker in a repairing plant of a power supply bureau checked the MД-16 bridge, he only turned off the bridge switch and did not open the power switch. When the bridge was turned over, his right hand touched the live part of the power end of the bridge , Due to the grounding of the electric bridge, the staff put an insulating pad under their feet, and they were separated from the power supply, only causing electric shock and burns from the energized loop from the ring finger of the right hand to the palm of the left hand.
5. Before the pressure test, the relevant personnel must be notified to leave the tested equipment or exit the site before proceeding.
High-voltage electrical test work is often carried out at the same time as other maintenance teams. Or it can be done right away, so before pressurization, these work teams must be notified to leave the tested equipment or exit the site, so that the tested equipment can be carried out in an unmanned state to achieve the purpose of ensuring the safety of personnel. These practices cannot be ignored, otherwise they will cause serious consequences.

For example, during the overhaul and test work of a transformer in a substation, the staff of the relevant team was notified before and after the transformer pressurization test, so that a maintenance worker thought that the equipment had no electricity and got on the transformer twice to work. This worker was just pressurized When I climbed the transformer again, I was fortunate to be found, avoiding electric shock.
6. The equipment under test with capacitance or electrical induction must be fully discharged or grounded before and after the test
The tested large-capacitance equipment such as: busbars, overhead cables, capacitors, etc. and equipment with electrostatic induction must be fully discharged or grounded after the high-voltage DC test is completed to prove that the tested equipment is indeed charge-free before it can work. Due to the high residual voltage or induced voltage of these devices, insulating rods must be used when discharging, which can also prevent accidental contact with live devices in operation. Some units did not pay attention to discharge or grounding, resulting in electric shock accidents.
For example, a technician in the high-voltage laboratory of a power plant conducts a 5-minute DC withstand voltage test of a 6-kV cable. The order of the numbers at both ends of the 5 adjacent cables to be tested is actually reversed, leaving hidden dangers. For example, one end is numbered 1 and the other end is 5, which has not been noticed. At the beginning, the test of a cable was completed. After disconnecting the test power supply, before discharging, the cable is not the tested cable from the serial number, but it is actually just after the test. The residual voltage is 25 kV on the cable head, so that it is left behind. The charge is electrocuted.
7. Pulling and closing of the pressure test work must be in response to each other, and the password must be correctly communicated
The pulling and closing operations of the pressure test work are more frequent. If you rely on subjective judgment or just look at the meter without listening to the password, or do not respond to each other and correctly communicate the password, an electric shock may occur.
For example, when the test team of a repairing plant of a power supply bureau conducts a transformer no-load test, the operator of the test power supply thinks that the line has been connected, and does not notify the switcher on the equipment, that is, close the test gate. When the switcher finds that the wiring is loose, Electric shock when disconnecting the wiring.
8. When the pressure test is reversed, the voltage regulator must be retracted to the zero position and the test power switch can be opened.
When the pressure test is working normally, when the wiring is switched, the voltage regulator must be adjusted to the zero position and the test power supply must be cut off. However, after searching for problems after the pressure, it is found that the wiring is not strong or the wrong wiring and the test power supply has a master switch. When there are split gates, some testers ignore them and cause accidents.
For example, when a power supply bureau’s substation construction team was doing an AC withstand voltage test of a substation booster switch, it found that the test data was problematic. In the process of finding the cause, the booster was not adjusted to the zero position, and the test power supply was not cut off. . When it was discovered that the polarity of the booster was incorrectly connected, the tester was about to change the polarity. The tester touched the live part pressurized to 50 kV. Fortunately, he got out of the power supply and only burned his hands without serious consequences.

XLPE insulated cable eccentricity control details

1. Wire drawing and twisting
Qualified products are not detected, but manufactured. For the control of 110kv cable eccentricity, each department in the cable enterprise has corresponding quality control responsibilities. Here we mainly talk about the understanding and detailed control of conductor preparation and tooling level. When designing a conductor, people give priority to or often only consider the reference conductor carrying capacity and conductor DC resistance. This is not enough for 110kv and above power cables. The roundness and straightness of the conductor often affect the XLPE insulation material. Distribution, which in turn affects the electric field distribution in the cable; the monofilament ductility of the conductor filaments will affect the cable insulation stress; the conductor surface quality (such as oxidation caused by improper storage, conductor knocks in the disk flow, etc.) on the current carrying capacity Wait. In the process of drawing, if the concentration and temperature of the emulsion are not regularly checked and replaced according to the standard, it is very likely that the monofilament will be oxidized in the drawing. In the conductor stranding process, the conductor protection is insufficient. Some companies have installed online DC resistance measuring instruments but do not use them. Some companies produce high-voltage cables according to the habit of producing low- and medium-voltage cables, even when they are producing 110kv cables because of the absence of staff on duty. , The personnel are transferred from the production line of low-voltage cables. These ideological understanding and detailed control will seriously affect the eccentricity control of the cable, but they are often ignored due to people’s experience. Uneven cable field strength distribution caused by scratches is an undesirable result.

2. Preservation and scientific use of insulating materials (including insulation, conductor shielding, and insulating shielding)
The transportation, storage and use of 110kv XLPE insulation material have strict requirements. The XLPE transportation link is not controlled by the cable company but is controlled by the cable material supplier. However, the cable company should also put forward corresponding requirements. The climate in the south is humid (install indoor temperature control equipment, balance humidity and temperature, and store cable materials at room temperature) and so on. When cable companies store XLPE cable materials, they should make unified arrangements and establish special insulation materials and shielding materials storage rooms to prevent material deterioration or abnormalities caused by climate change. There are only a handful of cable material companies in China that produce 110kv and above. Most of the ultra-high voltage XLPE insulation materials are imported from Borealis, Dow Chemical and other foreign companies. Due to language differences, most of the materials’ certificates are in English, and there is no Obvious production date and shelf life identification, using codes or codes that only cable material manufacturers can understand, this brings great inconvenience to cable material users. When the cable material is used in batches, the most contacted cable material is Workshop operators rarely understand English. The author had previously suggested a cable material foreign company, but only got a vague answer. This is because UHV cable materials belong to the seller’s market and are monopolized by a few companies. It is recommended that domestic cable companies must clarify the transportation conditions, production date, shelf life and Chinese-English bilingual instructions when purchasing UHV cable materials. In addition, XLPE insulation, shielding material storage rooms and inter-connection operation rooms should be prohibited from entering and exiting non-duty operators as much as possible. When there are special circumstances, dust removal work must be done to avoid cable breakdown due to a strand of hair. If conditions permit, companies can install monitors in the storage room to increase assessment efforts so that all employees can realize the huge impact of high-voltage and ultra-high-voltage insulation materials on cables.
3. Process technology
The XLPE insulated cable cross-linking production line in the cable industry in the world basically has two methods: catenary and tower. In recent years, the discussion of which is better for catenary and tower has been going on. According to public information, if China Nearly 60 vertical towers have all cross-linked lines in full production, which can meet the world’s demand for high-voltage and ultra-high-voltage cables. Therefore, the 21st order of the Development and Reform Commission in 2013 on the addition of 6KV and above dry-type cross-linking production lines to the cable industry limits.
The technical factors that affect the eccentricity of the cable insulation also include: the specifications of the extrusion die, the stress of the XLPE insulating material, the operating temperature and speed of the cross-line, the skill level of the operators, and so on.For more cable knowledge, please follow Chris’s cable.

Can bus ducts replace cables?

Overhead cables play a pivotal role in power systems, information transmission systems, power communications and other systems. However, due to the appearance of bus ducts in recent years, many people think that bus ducts can replace wires and cables in the future. Is it really possible? Let’s talk about the difference between the two in detail below.
Overhead  Cable:
Overhead cables are used to transmit electric (magnetic) energy, information and wire products that realize electromagnetic energy conversion. Wires and cables in a broad sense are also referred to as cables for short. Cables in a narrow sense refer to insulated cables, which can be defined as: an aggregate composed of the following parts; one or more insulated cores, and their respective coatings. The protective layer and the outer protective layer, the cable can also have additional uninsulated conductors.


Busway:
The bus duct is a closed metal device composed of copper and aluminum bus bars, which are used to distribute high power to the various components of the dispersion system. It has become popular in developed countries abroad, as well as Hong Kong and Macau in my country. In Guangzhou, Guangdong, my country, where the power distribution room of buildings above 12 floors is out of line, more than 90% of the main trunk lines leading to the floor use bus ducts; 630KVA transformers must use bus ducts to the power distribution cabinet.
Busway has many advantages, and it is widely used in low-voltage power distribution system transmission trunk projects, and it is increasingly replacing cables. Compared with the technical performance of the cable or the pre-branch cable, the busway has the characteristics of good heat dissipation, low impedance and large current carrying capacity. Comparing the technical performance of bus ducts with a current-carrying capacity of 630A or higher with cables or pre-branched cables above 630A, under the same current-carrying capacity, copper can be saved by 10-35% and power loss can be reduced by more than 15%.
For this reason, bus ducts have been widely used in power transmission trunk projects of low-voltage power distribution systems, and have increasingly replaced wires and cables. But in other fields, the advantages of ABC cables are obviously more obvious, so it is impossible for bus ducts to completely replace wires and cables.

Aluminum alloy cable, copper cable, aluminum cable, who is the main ups and downs

High-quality aluminum alloy conductor sales rods are the decisive factor for the electrical and mechanical properties of aluminum alloy cables. Without high-quality aluminum alloy rods, no matter how the drawing, stranding, cabling, armoring, etc. are in the subsequent processes, they cannot be changed. The basic quality of its conductor. Aluminum alloy cable manufacturers must have an alloy formula that meets the production of AA8000 series conductor aluminum alloys, and have conductor aluminum alloy rod smelting, continuous casting and rolling production lines. That is to say, they can produce conductor aluminum alloy materials. If an enterprise does not have this basic ability, where do the rods come from? The quality of the rod material is fundamentally uncontrollable. How can we produce qualified aluminum alloy cable products? The products of this kind of enterprise are really worrying.


In terms of use, there is a big difference between aluminum alloy cables AWG and copper cables. Everyone is very familiar with copper cables. They are made of a single metal material. After decades of application, the application technology of copper cables and the supporting accessories such as connecting terminals have become very mature. Because the conductor of the aluminum alloy cable is made of aluminum alloy material, there is currently no accessory products such as aluminum alloy copper connection terminals that are consistent with the performance of the alloy cable. Currently, the industry uses copper-aluminum transition terminals that were originally used to connect aluminum cables and the recent so-called high-conductivity microalloy copper transition terminals that only improve the conductivity of the terminals (the aluminum alloy terminals are also claimed to be external, but the concept is actually confused). In fact, these application schemes are extremely wrong. Aluminum alloy cable is a new type of conductor material invented to improve the physical, mechanical, compressive creep resistance and other properties of pure aluminum cables, and there are hidden safety hazards in use. Now the application of aluminum alloy cables uses aluminum in the connection. Or the so-called non-conducting aluminum alloy that is inconsistent with the performance of the aluminum alloy cable is used as the connection, then all the defects of aluminum or non-conducting aluminum alloy still exist, and the hidden safety hazard still exists. As we all know, the potential safety hazards of cables in applications basically lie in the connection. At present, because of the existence of aluminum or the so-called non-conducting aluminum alloy in the connection of aluminum alloy cables, the advantages and value of aluminum alloy cables cannot be used and reflected at all. What is the difference between this and the direct use of aluminum cables? The truly correct and perfect connection scheme is to use aluminum alloy copper connection terminals that are consistent with the performance of the aluminum alloy cable as the connection accessory.

After comparing aluminum alloy cables and copper cables, let’s look at aluminum alloy cables and aluminum cables. There is a saying in the market that aluminum alloy cables are better than aluminum cables, even if the quality is a little bit worse, it does not matter, in fact, it is far from the case. Aluminum alloy cables that do not meet the requirements of the national industry standard for aluminum alloy cables “Rated Voltage 0.6-1kV Aluminum Alloy Conductor Cross-linked Polyethylene Insulated Power Cable” are unqualified products and are genuine fake and inferior products. Perhaps many users do not know that unqualified aluminum alloy cables are actually inferior to aluminum cables, because the base material of conductor aluminum alloy is aluminum, and conductor aluminum alloy is based on the core technical formula and process by adding other metal elements to aluminum and then alloying and smelting. , New materials made by casting and rolling, qualified conductor aluminum alloy materials can return to the level of aluminum after electrical properties are processed, and their physical and mechanical properties are much better than aluminum. Unqualified so-called aluminum alloys cannot be restored to the level of aluminum because of their lack of core technology, mature production technology and professional production equipment. Due to alloy formula, smelting, processing technology and other reasons, the electrical properties of the produced aluminum alloy cannot be restored to the level of aluminum. , The mechanical properties cannot be effectively improved, and the overall performance is not as good as aluminum. Therefore, it is better to use aluminum cables than unqualified aluminum alloy cables. After all, aluminum cables are more economical and safer than unqualified aluminum alloy cables.
Although aluminum alloy cables have been hyped up, in fact, there are only a handful of professional manufacturers with alloy cable intellectual property technology and equipment in the country that can produce qualified alloy cables. From the perspective of cost, the cost of qualified aluminum alloy conductors is similar to that of high-quality electrolytic copper. The cost advantage of aluminum alloy cables over copper cables is mainly that cables of different lengths can be produced with the same weight of materials. For unqualified so-called alloy cables, the cost of conductor materials is basically the cost of aluminum materials. For unqualified alloy cables in the market, firstly, the conductor material is unqualified. Secondly, because the manufacturer does not have core formula technology, mature alloy cable production technology and production technology, the alloy cable products produced cannot meet the requirements of qualified alloy cables. It can be said that it is fundamental It is not a real aluminum alloy cable. Such fake and counterfeit products can only be sold at low prices.

A small solution for repairing damaged insulated and sheathed cables

1. Scope of application
When the PVC insulation layer and sheath layer of the overhead cable have local defects, they are allowed to be repaired, such as broken glue, collapsed pits, disconnections, wrinkles, bumps, ears, edges, breakdowns, joints, etc.
2. Use the same plastic strips, skins, blocks and tubes for materials and equipment raw materials. The raw materials should be smooth, clean, and free of other defects. The instruments used are fine wooden files, knives, scissors, pliers, screwdrivers, copper sheets or flat and smooth cable paper. The power of hot-air plastic welding torch, electric soldering iron and welding torch for plastic welding is above 300W.
3. The repair method of local defects
Repair methods such as breakdown points, holes, and collapse pits. Repair defects with a knife and cut into plastic blocks of the same size with a slope of 45°, place them on the repair area, fix them with pliers or a screwdriver, and then use a hot air speed welding gun to continuously weld them, and use copper sheets to compact and compact them. ,To flatten. When welding plastic, pay attention to the hot air temperature of the welding torch not to be too high to avoid scorching of the plastic in the repaired area. The repaired defect is tested by a spark machine, and it is qualified if it does not break down. Use a knife to cut the defect of the plastic layer into a slope of 45°, remove the plastic block or strip with the same shape, color and thickness, and fix it with pliers or a screwdriver. After completion, connect it with a hot-air speed welding gun, then use a copper sheet to compact, compact, flatten, and finally pass the spark machine test, and it is qualified if it does not break down. Scrape the plastic defect flat with a knife, fill in the recessed part with the same plastic strip under the action of a hot-air plastic welding gun, and then flatten, compress and compact the defect repair place with a copper sheet. After the spark machine test, no breakdown Is qualified.


4. The repair method of large joints
1) Repair of general large joints: use a knife to cut the plastic layer on both sides of the broken plastic layer into a slope of 45° along the circumference, and take it clean, the color and thickness are the same, and the length and outer diameter are the same as the broken glue. The plastic pipe is cut on one side of the pipe to form openings with an angle of 45° to each other. Put it at the glue break, tie it at equal distances with a thin copper wire, and then use the same plastic strip to be welded by a hot-air plastic welding torch. After welding, use copper sheet to compact, compact and flatten. It is qualified if it does not break down after the spark machine test.
2) Repair of large joints in the production process: During the production process, due to other reasons, the temporary stop, the sheath is disconnected, and the joint can be continuously connected. The method is to cut the plastic sheath into a circular slope with a 45° angle, retreat to the machine head, extend it into the mold core mouth for 30mm, and then run the glue. After the glue is run, the crew will cooperate with each other and drive the car. Connect the plastic layers by hand, and then reshape and repair.
3) Quality defects appear in the longer length of the cable sheath from one end, and most of the sheath of the other broken end is good, and the cable length is fixed, and the large joint repair method in the production process can also be used. Only after removing the defective end of the sheath, select a larger mold on the extruder, according to the process, first extrude the end of the sheath, and gradually increase the traction speed to the large joint so that the sheath at the interface gradually It is thinned and wrapped on the original sheath that is cut into a slope shape, and it will be reshaped and repaired after the machine is off.

Why do mice like to bitepower cable?

Rats are animals that everyone shouts and beat in our daily lives. Not only do they like to steal food, they also bite. If the electrical appliances in the house are suddenly out of use, it goes without saying that the eighth achievement is that the mouse bit PVC Insulated LV Power Cable, but why Do mice like to bite wires so much? Are you not afraid of being electrocuted?
In fact, mice don’t just bite wires, wood, cardboard boxes, and plastic products. They don’t let go; this is because mice have large incisors and can grow continuously. They grow about 3 cm in about a month, so they have to keep going. Bite things to grind their teeth. Otherwise, when the teeth grow to a certain extent, the mouse’s mouth will not close, and then starve to death. It can be said that the mouse has been gnawing and gnawing all his life and can’t stop at all.


Why are they not electrocuted?
Generally speaking, a mouse will not bite aaac wires at the same time. At this time, a current loop cannot be formed. Naturally, the mouse will not be killed by electricity. If the mouse bites a live wire, because the mouse’s hair and soles have relatively strong insulation, the current cannot There is no way to electrocute the mouse by forming an electric potential difference on the mouse.
How to prevent the wires from being bitten by mice?
In order to prevent this from happening, you can bury the wires in the wall during decoration to reduce the chance of mice contacting the wires. All kinds of wire troughs, power distribution cabinets, electrical appliances, etc. must be blocked to prevent rats from getting drilled. Go in; in addition, keep the room clean and sanitary, which can also effectively reduce the breeding of mice.

How to find broken overhead cables

The core of the cable is an important part of overhead cable. We transmit information through the core of the cable. If the core of the cable is broken, it will bring a lot of troubles and dangers. If the core of the cable is broken, how should we check? Someone may I would say to take a multimeter, but if it’s a big project, can’t I also use a multimeter?
One, the method of energizing the capacitor
Some cable factories usually use the capacitance comparison method to find the approximate location of the disconnection. Using continuous power-on method to accurately determine the disconnection point of the cable, the efficiency of this method is very low. Generally, it takes about one and a half hours to find a disconnection point. With this method, it is almost impossible to find a broken core for flame-retardant cables whose shielding, armoring, and sheathing processes have been completed. If it is not done properly, the flame-retardant cable will be scrapped. This method is basically no longer needed.


2. Combination of capacitance method and induction method
This method is used for the broken core of the cable core, which requires that LV ABC  cable core is not covered with a metal layer and there is no extruded sheath. When searching, first use the capacitor to find the approximate location of the cable disconnection, and then use the induced voltage method to accurately find the disconnection point. This method is very simple and quick, and it is also the most used method at present. The induction voltage method is to connect one end of the broken core of the cable with an AC voltage of 650V, and the other end and other cores are grounded, and then test with a sensor pen that can emit light signals. When the sensor pen slides over the broken core during the test, The signal will change, so that the cable break point can be accurately found.


3. Combination of constant current source and bridge method
This method is used for finished cables or cable cores that have been coated with a metal layer. Use is to find the method is to burn the insulation at the broken core of the flame-retardant cable with a constant current source and breakdown, and then use the bridge method fault locator to accurately locate the fault point, which is also a frequently used method.

How to prevent the control cable from overloading and catching fire

As the main carrier of power transmission, industrial control cables can be widely used in all aspects of our daily lives. However, during the operation of industrial control cables, resistance heating tends to occur. However, the temperature that the wire can withstand is limited, and if it exceeds a certain temperature, there will be greater danger. For example, when the current is overloaded, it will cause overheating. When the overheating reaches a certain level, it will cause high-temperature combustion and cause a fire. So how to effectively prevent industrial control cables from catching fire due to overload?

1. In the process of industrial control cable design, the capacity of the site should be accurately verified, and the possibility of adding capacity in the future should be fully considered, and the appropriate type of wire should be selected. For large capacity, thicker wire should be selected. Industrial control cable design and reasonable selection are the key steps to prevent overload. If the design is not properly selected, it will leave inherent hidden dangers that are difficult to rectify. Some small projects and places are not carefully designed and selected. It is very dangerous to choose and lay industrial control cables at will. New electrical appliances and electrical equipment should fully consider the capacity of the original lines. If the original line does not meet the requirements, it should be redesigned and remodeled.
2. Industrial control cables should be laid by qualified electricians in accordance with relevant specifications. The laying conditions of industrial control cables directly affect the heat dissipation of the wires. Generally speaking, the laying of industrial control cables should not pass through flammable and combustible materials and stacks, which will cause poor heat dissipation of the wires, heat accumulation, and the possibility of igniting the surrounding combustible materials, which increases the risk of fire under overload conditions. The wiring in the decoration ceiling of public places should be protected by steel pipes to separate the ceiling from the circuit. In the case of overload, short circuit, etc., the molten beads will not fall to avoid fire.
3. Strengthen power management, avoid random wiring and wiring, and use mobile sockets with caution. Random wiring, random wiring, and use of mobile sockets are actually adding electrical equipment to a certain section of the line, which increases the amount of current and may cause overload. There are obviously more mobile sockets than fixed sockets on the wall. If too many electrical equipment are used on the mobile sockets, the original wiring must be unbearable. For larger power equipment and electrical appliances, separate industrial Concentric Cables should be installed, and mobile sockets should not be used as wiring sources.
4. Speed ​​up the renewal and transformation of old lines to eliminate fire hazards. In old enterprises, old residential areas and other units, many industrial control cables have been aging and have exceeded their service life due to their long use time. Even if the current-carrying capacity of some lines is not large, the aging circuit can hardly withstand such current-carrying capacity, and it also has the danger of overload. Especially in old residential areas, industrial control cables have long been aging, but with the improvement of people’s living standards and the increase of household appliances, their electricity consumption is still increasing year by year, which is really worse. For old lines, timely supervision and coordination should be carried out, and rectification should be promoted as soon as possible to eliminate fire hazards and ensure safety.
The content introduced above is to effectively prevent industrial control cables from catching fire due to overload. In order to effectively ensure that the industrial control cable catches fire due to overload, you must have the above problems in your daily use. Once these problems are found, you need to replace new cable products and take other guarantee measures in time. , So that we can effectively prevent the fire from happening and ensure the safety of our lives

 

Smart grid boosts urban green development

In the future, smart cities will not only focus on high-efficiency and intelligent goals, but also include green, environmental protection and low-carbon development goals. The construction of smart grids will promote the green development of cities. With uneven energy distribution, a strong smart grid can greatly improve the grid’s ability to accept clean energy and optimize the allocation of energy resources on a large scale. More and more smart cities in our country are incorporating clean energy into the overall planning of smart cities. Especially abc cables played a huge role in this plan,realize the transformation of the economic development direction and the optimization and upgrading of the industrial structure. The goal is to build a modern and fully internationalized world ecological garden city, and the goal is to build a smart, green, and low-carbon livable city.


In the process of realizing the smart grid to promote urban green development, power cables play a prominent role in the construction of smart grids,the State Grid took the lead in practicing and established the National Wind and Solar Storage and Transmission Demonstration Project. The project is currently the world’s leading new energy comprehensive utilization platform integrating wind power, photovoltaic power generation, energy storage, and smart power transmission. Wind power will reach 1 million kilowatts, the total scale of photovoltaic installations will reach The scale reaches 110,000 kilowatts.


There are many participants in the construction of smart grids. With the construction of smart grids, its R&D and manufacturing levels will continue to improve, and the overall strength of the aaac industry will continue to improve. City-related industries will also develop rapidly and share market shares, creating conditions for smart grid-related industries to enter the international market. In addition, the improvement of the safe and stable operation of the power grid, the improvement of power supply reliability, and the high-quality power supply have also laid the foundation for the rapid growth of traditional industries and the rise of high-tech industries.