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How to repair cable faults after locating the fault point
2024-07-22The cable fault tester under Wuhan UHV can help many power workers conduct various power tests more conveniently.After locating the fault point, the steps for repairing the cable fault need to be carried out clearly and orderly to ensure the repair effect and safety. The following are the cable fault repair steps summarized based on relevant information:1、 Preparation stageSafety measures:Ensure that the power has been cut off and hang warning signs such as' Do not close '.Wear personal protective equipment such as insulated gloves, insulated boots, goggles, etc.Prepare necessary tools and equipment, such as insulation resistance tester, cable fault locator, high-voltage adhesive tape, insulation resin, etc.Fault point confirmation:Based on the positioning results, confirm the location and damage of the fault point again.2、 Repair stepsClean up the site:Clean up the debris and dirt around the fault point to ensure a clean working environment.Fault handling:Local damage: If the
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How to calculate the capacity of series resonance
2024-07-19The series resonance under Wuhan UHV can help many power workers conduct various power tests more conveniently.The capacity calculation of series resonance mainly involves parameters such as inductance, capacitance, and resonant frequency in the circuit. The following is a clear and detailed calculation process, taking into account the relevant numbers and information in the article:1、 Basic formulaIn a series resonant circuit, the relationship between the resonant frequency f, inductance L, and capacitance C is given by the following formula:[ f = \frac{1}{2\pi \sqrt{LC}} ]Among them, f represents the resonant frequency, L represents the inductance value, C represents the capacitance value, and π is the pi.2、 Calculate capacitance valueIf the inductance value L and resonant frequency f are known, the required capacitance value C can be deduced by the above formula:[ C = \frac{1}{4\pi2 f2 L} ]This formula is used to calculate the capacitance value required to achieve a resonant state a
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What equipment is needed for communication withstand voltage testing
2024-07-18The series resonance under Wuhan UHV can help many power workers conduct various power tests more conveniently.AC withstand voltage test is an important method for evaluating the insulation strength of power equipment. There are various types of equipment required, and the equipment selected may vary depending on the test object and requirements. The following is a clear summary and point representation of commonly used equipment for AC withstand voltage testing:1、 Main equipmentVariable frequency series resonant withstand voltage test deviceComposition: The device mainly consists of excitation transformer, variable frequency power supply, high-voltage reactor, capacitive voltage divider, compensation capacitor and other components.Features: Suitable for testing with high capacity and low voltage requirements, especially for AC withstand voltage testing of cable long distance specimens. The required capacitance and voltage can be calculated based on parameters such as voltage level, cr
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What are the causes of faults in buried cables
2024-07-17The cable fault tester under Wuhan UHV can help many power workers conduct various power tests more conveniently.The causes of faults in buried cables can be summarized into the following aspects, which will be explained in detail with relevant numbers and information:1、 External force damageMain reason: External force damage is the main cause of faults in buried cables. This includes activities such as repeated construction, laying water pipes, constructing water channels, planting trees, and building structures above buried lines, which can easily damage the insulation layer of the buried lines and cause wire breakage or grounding faults.Specific examples: Mechanical collisions, excavation, and other behaviors during construction, as well as natural factors such as earthquakes and soil settlement, can all cause damage to buried cables.2、 Connector malfunctionConstruction issues: Due to non-standard joint technology during construction, it is highly likely to cause mechanical damage o
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What are the preventive measures for buried cable faults
2024-07-16The cable fault tester under Wuhan UHV can help many power workers conduct various power tests more conveniently.The preventive measures for buried cable faults should be comprehensive and detailed. The following are some specific preventive measures, summarized in a clear format:1、 Preventive measures during the design and construction phasesReasonably design cable routesWhen designing cable lines, sufficient investigation should be conducted to collect soil data from the areas where the lines pass through, and chemical analysis should be carried out to determine the degree of soil and groundwater erosion.Based on the allowable ambient temperature of the cable conductor, laying conditions, losses and thermal resistance of each part, and the number of parallel circuits, the current carrying capacity of the cable line should be calculated reasonably, and an appropriate laying depth should be designed to avoid problems caused by being too shallow or too deep.Select high-quality cablesSel
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How to determine the specific location of buried cable faults
2024-07-15The cable fault tester under Wuhan UHV can help many power workers conduct various power tests more conveniently. Determining the specific location of a buried cable fault is a complex and meticulous process that requires the comprehensive use of multiple methods and tools. The following is a clear judgment process, summarized based on relevant numbers and information:1、 Preliminary diagnosis of malfunctionCollect information:Understand the basic information of cables, including cable model, specifications, laying method, service life, etc.Inquire about the specific situation at the time of the malfunction, such as whether there were any abnormal sounds, whether there was a fire, etc.Appearance inspection:Conduct a visual inspection of the cable circuit to see if there are any obvious signs of damage, burning, or deformation.Check key parts such as cable joints and terminals for oil leakage, corrosion, or poor contact.2、 Determination of fault typeUsing testing instruments:Use testing
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Comparison of parallel power supplies and series power supplies
2024-07-12Series resonance under Wuhan UHV can help many power workers conduct various types of power tests more conveniently.The application of parallel power supplies and series power supplies in circuits each has its own characteristics and advantages. The following is a detailed comparison of the two:1. Definition and connection methodParallel power supply: Connect the positive poles of multiple power supplies in parallel, connect the negative poles of multiple power supplies in parallel, and connect the positive and negative poles of each power supply to each other. In this connection mode, the output voltage of each power supply is the same and the current can be divided.Series power supply: Connect the positive and negative poles of multiple power supplies in sequence to form a series circuit. In this connection mode, the voltage of the overall power supply is the sum of the voltages of the individual power supplies, and the current remains unchanged.2. Voltage and current characteristics
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How to choose a series resonant device
2024-07-11The series resonance under Wuhan UHV can help many power workers more conveniently conduct various power tests.When selecting a series resonant device, multiple factors need to be considered to ensure that the selected equipment can meet practical needs and has good performance and reliability. The following is a clear selection guide that combines relevant numbers and information from the article to summarize:1、 Clarify requirements and test objectsVoltage level:Determine the voltage level of the test object, such as 10kV, 35kV, 110kV, etc. Test objects of different voltage levels require series resonant devices of corresponding voltage levels.Reference number: For example, for a 110kV power transformer or cable, it is necessary to select a series resonant device that can output the corresponding voltage.Experimental nature:Understand the specific properties of the test, such as neutral point withstand voltage, full insulation withstand voltage, etc.The configuration and parameters of
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What are the measures to accelerate cable fault repair
2024-07-10The cable fault tester under Wuhan UHV can help many power workers to conduct various power tests more conveniently.The measures to accelerate cable fault repair are multifaceted, aimed at improving the accuracy of fault location, accelerating repair speed, and minimizing the impact on the power grid and users. Here are some specific measures:1、 Establish an efficient fault repair command systemEstablish a fault repair command center: Based on the number of cable faults, a dedicated fault repair command center or dispatch center can be established to be responsible for the repair command and coordination work of various departments.Provide reliable communication equipment: Ensure that the command center can timely obtain repair information and maintain smooth communication with the repair site, so that the material and logistics departments can timely understand the situation of the repair site.2、 Develop standardized emergency repair proceduresDevelop standardized emergency repair sof
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How to improve the accuracy of cable fault location
2024-07-09The cable fault tester under Wuhan UHV can help many power workers to conduct various power tests more conveniently. Improving the accuracy of cable fault location is the key to ensuring rapid cable repair and reducing power outage time. The following are some specific measures and methods aimed at improving the accuracy of cable fault location: 1、 Adopting advanced fault location technology Pulse reflection method: Using the principle of high-frequency pulse signals propagating and reflecting in cables to identify faults. When a pulse signal encounters a fault point, reflection occurs. By measuring the time and speed of the reflected signal, the location of the fault point can be calculated. This method has high positioning accuracy and is suitable for various types of cable faults. Impulse high-voltage flashover test method (impulse flashover method): suitable for most flashover faults, open circuits, low resistance, and short circuit faults. By applying a high-voltage si
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The concept and composition of series resonance
2024-07-08The series resonance under Wuhan UHV can help many power workers more conveniently conduct various power tests. Series resonance is a very important concept in electronic circuits, which involves the interaction of inductance, capacitance, and resistance in the circuit. The following is a detailed explanation of the concept and composition of series resonance: The concept of series resonance Series resonance refers to the phenomenon in which the voltage and current in a circuit reach their maximum value at a specific frequency after being connected in series by an inductor (L), capacitor (C), and resistor (R) in a certain order. This specific frequency is called the resonant frequency. At the resonant frequency, the impedances of inductance and capacitance cancel out each other, minimizing the total impedance of the circuit, resulting in an increase in current and a corresponding increase in voltage. At this point, the circuit exhibits a special property, where the energy in
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What are the functions of the four components of series resonance
2024-07-05The series resonance under Wuhan UHV can help many power workers more conveniently conduct various power tests. The four main components of series resonance include excitation transformer, voltage divider, variable frequency power supply, and high-voltage reactor. These components play crucial roles in series resonant circuits, together ensuring the normal operation and functionality of the circuit. Here are their specific functions: Excitation transformer: Function: The main function of the excitation transformer is to boost the voltage output by the variable frequency power supply to meet the needs of high-voltage testing or measurement. At the same time, it can also play a role in isolating high and low voltage, ensuring the safety of the circuit. Importance: As a crucial component for boosting and isolating, the excitation transformer is crucial for the stable operation of series resonant circuits. Voltage divider: Function: The voltage divider is used to measure
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How do the four components of series resonance work together
2024-07-04The series resonance under Wuhan UHV can help many power workers more conveniently conduct various power tests. The working mechanism between the four components of series resonance (excitation transformer, voltage divider, variable frequency power supply, and high-voltage reactor) is coordinated and closely coordinated, jointly realizing the resonance phenomenon in the circuit. Here is a detailed explanation of how they work together: 1. Variable frequency power supply Function: The variable frequency power supply is the control center of the entire series resonant device, which converts 220V/380V, 50HZ power supply into frequency adjustable and continuously adjustable voltage output. This adjustability allows the variable frequency power supply to adjust output parameters according to different experimental or measurement needs to achieve the best resonance effect. Working mechanism: The variable frequency power supply adjusts the output frequency and voltage through int
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Application of series resonance and parallel resonance
2024-05-07Series resonance under Wuhan UHV can help many power workers more convenient for all kinds of power testing. Series resonance and parallel resonance are common resonant phenomena in circuits, and they have important applications in circuit design and analysis. In this article, we will introduce the applications of series resonance and shunt resonance, and provide analytical methods to solve the problem. Series resonance applications: Series resonance is a phenomenon in which inductive and capacitive elements in a circuit are connected in series to form a resonance phenomenon. Series resonance plays an important role in the following applications: Filter design: series resonant circuits can be used to design filters for filtering out signals in a specific frequency range. For example, in audio circuits, series resonant circuits can be used to design low-pass filters to remove high-frequency noise. Signal Generators: Series resonant circuits can be used to design signal generators that p
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DC withstand voltage precautions
2024-05-07Series resonance under Wuhan UHV can help many power workers to carry out all kinds of power tests more conveniently. DC withstand voltage refers to the voltage range that the circuit components can withstand when a DC voltage is applied to the circuit. DC withstand voltage is an important parameter in circuit design and analysis, which is vital to ensure the stability and reliability of the circuit. In this article, we will introduce the precautions for DC Withstand Voltage and provide an analytical approach to solving the problem.Precautions:When conducting DC withstand voltage testing, the following matters need to be noted:Voltage selection: according to the rated voltage and voltage withstand level of the circuit components, select the appropriate DC voltage for testing.Test methods: Choose appropriate test methods, such as voltage sources, oscilloscopes or special test instruments, to accurately measure the DC withstand voltage values of circuit components.Safety measures: When c
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What is surfactant
2024-05-06UHV-670 Transformer Oil Surface Tension Tester under Wuhan UHV can help many power workers more convenient for all kinds of power testing. Surfactant (surfactant), also known as interfacial active agent, is a kind of compound that can make the surface tension (surface tension) or interfacial tension (interfacial tension) between two liquids, liquid-gas, liquid-solid significantly reduced. They have a special molecular structure with hydrophilic groups at one end and hydrophobic groups at the other. Hydrophilic groups are often polar groups, such as carboxylic acid, sulfonic acid, sulfuric acid, amino or amine groups and their salts, hydroxyl, amide, ether bonds, etc.; and hydrophobic groups are often nonpolar hydrocarbon chains, such as more than 8 carbon atoms hydrocarbon chain. This structure is called "amphiphilic structure", which allows surfactants to interact with both water and oil. Surfactants have a variety of applications and functions, such as wetting, penetrating, emulsifyi
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Surface Tension Test Principle
2024-05-06UHV-670 Transformer Oil Surface Tension Tester under the WuhanUHV can help many power workers to carry out all kinds of power tests more conveniently. Bubble pressure method: This method measures surface tension by determining the radius of curvature of the bubble changes with the pressure of inert gas during the generation and development of bubbles in the liquid. When the shape of the bubble is exactly hemispherical, the radius of curvature of the bubble is minimized and exactly equal to the capillary radius. At this point, the surface tension of the liquid can be deduced by measuring the maximum pressure required for the bubble to detach from the end of the tube.Suspended Drop Method: This method derives the surface tension of a liquid by measuring the contour of a droplet suspended above the liquid. The shape of the droplet has a close relationship with the surface tension, so by accurately measuring and analyzing the contour of the droplet, the surface tension of the liquid can be
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What are the solutions to common faults
2024-05-06UHV-500 Cable Fault Location Detector under Wuhan UHV can help many power workers to carry out all kinds of power tests more conveniently. The solutions for cable faults mainly include the following aspects:Fault location and diagnosis: Use professional cable fault testers, such as local voltage test, insulation resistance test, resistance test, oscilloscope test, etc., to accurately find out the fault point. For buried cables, equipment such as underground conductor fault measuring instrument and buried cable abnormal position indicator can be used to determine the fault location.Repair or Replacement: Once the fault point has been identified, repair work can be carried out if it is due to external damage or insulation aging. Repair includes steps such as cleaning the fault point, reconnecting or repairing the insulation. If the cable is severely damaged or the cost of repair is too high, consideration should be given to replacing the cable with a new one.Preventive measures: Strength
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What factors easily lead to cable failure
2024-05-06UHV-500 Cable Fault Location Detector under Wuhan UHV can help many power workers to carry out all kinds of power tests more conveniently. The occurrence of cable failure may be caused by a variety of factors, the following are the main categories of factors:Mechanical damage: Cables may be damaged by external forces such as excessive bending, stretching, digging, piling, etc. during installation, transportation and use, resulting in structural damage or even direct damage to the cable. In addition, vehicle vibration or shock load may also cause damage to underground cables.Damp insulation: Damp insulation is one of the common causes of cable failure. This can be due to poor sealing of the splice or terminal boxes that allows moisture to enter the cable, or manufacturing defects such as holes or cracks in the metal sheath that allow moisture and humidity to enter the cable. High ambient humidity and poor drainage in the cable laying area can also lead to moisture in the cable.Aging and
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The reason of resonance point can't be found
2024-05-06Resonant Test System under Wuhan extra high voltage can help many power workers more convenient for all kinds of power testing. Resonance point can not be found for a variety of reasons, the following is a list of possible reasons: Equipment resonance point beyond the host output frequency range: this may be due to the equipment resonance frequency and host output frequency range does not match, resulting in can not find the resonance point. The test device is wired incorrectly: the series resonance test device contains components such as the test host, excitation transformer, reactor, voltage divider cylinder, etc., and the connecting wires are required to connect each device with the cable under test. If the wiring is not correct, not only may not be able to measure the resonance point of the cable, but also easy on the service life of the device, and may even burn out the equipment. The device is not reliably grounded before the test: poor grounding of the device may lead to electri
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