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Introduction to issues related to circuit resistance
2024-09-19The circuit resistance tester under UHV power can help many power workers conduct various power tests more conveniently.What does circuit resistance mean?The DC circuit resistance is the total resistance of two conductors that form a circuit at one end of the link. This is usually a function of the conductor diameter, which varies only with distance. DC resistance is often confused with impedance, which is a term used to describe the dynamic resistance of a signal flow, typically at a specified frequency.What is cyclic testing?Loop testing is defined as a type of software testing that focuses entirely on the effectiveness of loop structures. It is one of the components of control structure testing (path testing, data validation testing, condition testing). Loop testing is a type of white box testing. This technique is used to test loops in programs.What is a circuit tester?We specialize in producing circuit resistance testers for ultra-high voltage power. You can contact ultra-high vol
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How to solve the fault of DC high-voltage generator?
2024-09-14The DC high-voltage generator under the UHV power company can help many power workers conduct various power tests more conveniently.DC high-voltage generators have the characteristics of small size, light weight, beautiful and reliable appearance, simple operation, and complete functions, and are widely used in the power sector of enterprises such as electric power, mining, metallurgy, and steel. Mainly conduct DC withstand voltage tests on high-voltage electrical equipment such as zinc oxide lightning arresters, power cables, transformers, generators, and high-voltage switches.As a large electrical equipment, DC high-voltage generators may encounter some common faults during use. First, let's talk about the common faults and solutions of DC high-voltage generators.1. Turn on the battery switch of the DC high-voltage generator, but the battery indicator light and green light are not on?Fault analysis: Check the battery fuse, battery cable, and battery switch;Solution: If there is a
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How to safely connect series resonant circuits?
2024-09-13The series resonance under UHV power can help many power workers conduct various power tests more conveniently.The frequency conversion resonance withstand voltage test device adopts a dedicated broadband voltage regulation power supply, with a voltage regulation range of ac0-400V, a frequency modulation range of 30-300Hz, and a frequency fineness of up to 0.1Hz; The output waveform within the entire frequency range is good, ensuring the stability and safety of the instrument at the minimum weight and volume. The device consists of a frequency and voltage regulating power supply, an excitation transformer, a reactor, and a capacitor voltage divider. The frequency conversion resonance withstand voltage test belongs to the high-voltage withstand voltage test. There are many things to pay attention to during the testing process. The circuit connection and precautions of the frequency conversion resonance withstand voltage test device are as follows:Through on-site testing of the full load
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Precautions for choosing a cable fault tester
2024-09-13The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.Cable fault tester is one of the commonly used devices for detecting cable faults. Its performance is stable, and it can quickly and accurately identify the fault point. Maintenance personnel can quickly carry out maintenance work, greatly improving work efficiency. The selection of cable fault testers is also a concern for many friends. Next, we will focus on introducing the precautions for purchasing.Another situation of power supply analysis: In recent years, 80% of cable fault testers have been damaged due to poor wiring or wiring errors caused by high-voltage flashing, resulting in high-voltage signals entering the host and causing instrument damage. If battery power is used, even if high-voltage signals enter, they do not form a circuit to the ground and can only cause common mode effects, thus completely avoiding machine damage accidents.Reasons why laptops and collec
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How to purchase secondary testing equipment?
2024-09-12We specialize in producing secondary testing equipment for UHV power. Next, we will share with you how to purchase secondary testing equipment?Testing qualification equipment is indeed a device that power companies are familiar with and familiar with nowadays. Such equipment can help power companies apply for testing qualifications, and there are different levels of testing qualification equipment. Testing qualification equipment is also essential, but it also includes other instruments that power companies need to understand.As long as one is familiar with the qualification equipment for testing, it can be found that such equipment still includes other instruments and equipment that can be understood by power companies now. Therefore, it is necessary to understand the list of instruments and equipment included in it. At present, power companies can easily search for and access relevant qualification equipment websites to search for such equipment, including being able to understand wh
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How to purchase primary testing equipment?
2024-09-12We specialize in producing primary testing equipment for UHV power. Next, we will share with you how to purchase primary testing equipment?Testing qualification equipment is indeed a device that power companies are familiar with and familiar with nowadays. Such equipment can help power companies apply for testing qualifications, and there are different levels of testing qualification equipment. Testing qualification equipment is also essential, but it also includes other instruments that power companies need to understand.As long as one is familiar with the qualification equipment for testing, it can be found that such equipment still includes other instruments and equipment that can be understood by power companies now. Therefore, it is necessary to understand the list of instruments and equipment included in it. At present, power companies can easily search for and access relevant qualification equipment websites to search for such equipment, including being able to understand which
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Types and diagnostic methods of internal faults in power transformers
2024-09-11Internal faults in power transformers can be classified into two types:Overheating and discharge faults. According to temperature, overheating faults can be divided into low-temperature overheating, medium temperature overheating, and high-temperature overheating. Discharge faults can be classified into high-energy discharge, low-energy discharge, and partial discharge based on their energy density. Three types.As for mechanical failures and internal water ingress and moisture, they will eventually develop into electrical failures.Overheating faults are caused by accelerated insulation degradation due to thermal stress.If thermal stress only causes the decomposition of insulating oil outside the heat source, the special gases produced are mainly methane and ethylene, which generally account for more than 80% of the total hydrocarbons. As the fault point increases, the proportion of ethylene will increase, and severe overheating will produce trace amounts of acetylene.When overheating i
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What is weak current engineering?
2024-09-11Power applications can be divided into strong power and weak power based on the strength of power transmission. The electricity consumption of a building complex generally refers to AC 220V 50Hz and above strong electricity. Mainly providing electricity for people, converting electricity into other energy sources such as air conditioning electricity, lighting electricity, power electricity, etc.There are mainly two types of weak electricity in smart buildings. One is low-voltage electricity such as national security voltage levels and control voltages, AC/DC, AC below 36V, and DC below 24V, such as 24V DC control power supply or emergency lighting backup power supply. Another type is information sources that contain voice, image, data, and other information, such as telephone, television, computer information, etc.People are accustomed to calling it weak current technology. It can be seen that the basic meaning of weak current technology in intelligent buildings is still the original w
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What is the MVA unit of electrical energy?
2024-09-10MVA in electricity is a unit of transformer capacity, power unit, or power unit generated by a generator.VA=WMVA=MW1MW=1000KW=1000000WKilowatt, an early unit of electrical energy, has a tendency to extend to the entire field of physics as a power unit. In electricity, kilowatt hour is exactly the same as degree, but with a different name.1 kW=1000 W=1000 J/s1 kW=1000 Newton meters per second (N m/s)1 kW=0.239 kcal/s1 kW=1.36 horsepowerWatt is a unit of power in the International System of Units. Watt is defined as 1 joule per second (1J/s), which is the rate at which energy (in joules) is converted, used, or dissipated per second. In the electrical unit system, it is volts multiplied by amperes multiplied by power factor (1V · A, abbreviated as 1 volt ampere).Unit conversion: Watt is named after British scientist James Watt, who made significant contributions to the development of steam engines. The name of this unit was first adopted at the 2nd meeting of the British Association for t
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Drying treatment method for transformers
2024-09-10The significance of transformer dryingThe purpose is to remove moisture from the insulation material of the transformer, increase its insulation resistance, and improve its flashover voltage. Transformers with voltages higher than 3kV must be dried.The transformer body is mainly assembled from iron core, coil, and insulation material. After assembly, before adding transformer oil, a drying process must be carried out to remove moisture and gas from the insulation material, so as to control the moisture content in the product quality within the limit, to ensure that the transformer has sufficient insulation strength and operation life. For high-voltage transformers, it is required that the moisture content of the insulation material be within 0.5%.Insulation drying standards and drying treatment for transformers(1) Drying standard:① Transformer insulation oil does not contain moisture. The breakdown voltage of the oil product shall not be lower than 75% of the factory data;② The insulat
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Three detection methods for capacitors
2024-09-09A capacitor is a device that contains an electric charge and is one of the electronic components used in a large number of electronic devices. Widely used in circuits such as DC, AC, coupling, bypass, filtering, tuning circuits, energy conversion, and control. The detection of capacitors is mainly divided into three categories: detection of fixed capacitors, detection of electrolytic capacitors, and detection of variable capacitors.1、 Fixed capacitance detection1. Detect small capacitors below 10pF. Because the fixed capacitance below 10pF is too small, measuring with a multimeter can only qualitatively check for leakage, internal short circuit, or breakdown. When measuring, a multimeter with R × 10k range can be used, and two probes can be connected to either pin of the capacitor. The resistance value should be infinite. If the measured resistance value (pointer swinging to the right) is zero, it indicates that the capacitor is damaged by leakage or internal breakdown.2. Check whether
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Under what circumstances would a gas chromatograph be used?
2024-09-09The oil chromatography analyzer under UHV power can help many power workers conduct various power tests more conveniently.In daily work, the sound of a gas chromatograph is often heard. When will gas chromatography be used, as this instrument has a wide range of applications in many industries? Gas chromatograph is a computer-controlled multi-purpose high-performance series chromatograph. Mainly used for quality inspection, scientific research, pollution inspection, and production control of industrial production intermediates and industrial products.Before using the gas chromatograph, open all glass ports of the titration cup and clean the titration cup, drying tube, and sealing plug with water. After cleaning, dry in an oven at approximately 80 ° C and then cool in a natural environment. Please note that the materials of the cathode chamber and measuring electrode should not be cleaned with water. It can be cleaned promptly with organic solvents such as acetone and methanol, and then
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The purpose, method, and precautions of transformer DC resistance testing
2024-09-06The DC resistance tester under UHV power can help many power workers conduct various power tests more conveniently.The purpose of testing the DC resistance of a transformer is to:1. Check the welding quality of the winding joints and whether there is a turn to turn short circuit in the winding;2. Whether the contact of each position of the on load tap changer is good, and whether the actual position of the tap changer is consistent with the indicated position;3. Whether the outgoing line is disconnected;4. For three-phase power transformers, calculate the unbalance rate of their three-phase DC resistance based on the test results to determine whether it meets the design or relevant standardsMeasurement of transformer DC resistance using a DC resistance testerMeasuring DC resistance is an important item in transformer testing. By measuring the DC resistance, the conductive circuit of the equipment can be checked for defects such as poor contact, poor welding, coil faults, and wiring err
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Product Description and Application Scope of DC High Voltage Generator
2024-09-06The DC high-voltage generator under the UHV power company can help many power workers conduct various power tests more conveniently.1、 Precautions for using discharge rods as supporting products for DC high-voltage generatorsWhen discharging a large capacitor sample, after the test is completed, disconnect the test power and wait for a period of time to allow the charge on the sample to self discharge to the ground through the voltage doubler and grounding terminal. The sample itself. It can be observed that the voltage reading on the voltmeter on the control box is gradually decreasing. When the voltmeter drops to a lower voltage, usually around 5Kv~15Kv, a discharge rod can be gradually moved to the vicinity of the tested product and discharged freely through air. At this time, a hissing sound can be heard. If there is no sound, the tip of the discharge rod can be used to contact the sample, and finally the sample can be directly discharged to the ground.2. The accumulated charge of
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How long does it take to retest the transformer
2024-09-05What tests should be conducted before putting a transformer into use if it has been out of service for one month or has been idle or out of service for more than six months?1. After the transformer is shut down for one month, the insulation resistance should be measured before resuming power transmission. Only after passing the test can it be put into operation.2. Transformers that have been idle or suspended for more than 6 months should undergo insulation resistance and insulation oil withstand voltage tests before being put into operation.3. The special service life of drainage and irrigation transformers in dry and cold areas can be appropriately extended, but not exceeding 8 months.What regulations must be followed for the operation and shutdown of transformers?(1) Newly commissioned transformers must undergo 5 impulse tests at rated voltage and 3 tests after maintenance.(2) When the transformer is put into operation, first place it in the cooler. The cooler runs for a period of t
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Operation and use of pointer type insulation resistance tester
2024-09-05The insulation resistance tester under UHV power can help many power workers conduct various power tests more conveniently.Insulation diagnosis is an important means of detecting insulation defects or faults in electrical equipment. The pointer type insulation resistance tester is a specialized instrument for measuring insulation resistance. At present, electrical equipment is developing towards high capacity, high voltage, diversified structure, and sealing.Operation and wiring method of pointer type insulation resistance tester:1) Before the experiment, the power supply and all external connections of the test equipment should be disconnected, and the test substance should be short circuited to ground and discharged for 1 minute. If the capacitance is large, it should be discharged for at least 2 minutes to avoid electric shock affecting the measurement results.2) Check if the instrument pointer is at infinity or adjust the mechanical zero screw.Attention: When adjusting the mechanic
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Preparation before battery internal resistance test
2024-09-04The battery charging and discharging tester under the UHV power company can help many power workers conduct various power tests more conveniently.There are many types of battery internal resistance testing equipment, and their main difference lies in the type of battery being tested. The capacity and terminal voltage of the tested battery are different. Here we are talking about the preparation before battery testing for power, communication, and UPS power battery testing1. Fully charge the tester and check if it is working properly2. Prepare some necessary maintenance tools and protective tools, such as insulation and fixing protective tools3. Check the historical records of the test battery. Many units may not have this record. It is currently unclear when the battery was installed and put into use, but you must do some homework to figure it out.4. Prepare some adhesive labels and conditionally write the model, internal resistance value, test date, and label on them.5. Bring a thermo
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Analysis method and results of factors affecting DC leakage
2024-09-041. The influence of high-voltage connecting lines on ground leakage currentDue to the fact that the wires connected to the test product are usually exposed to the air (without shielding), the pressurized end of the test product is exposed to the outside, so the surrounding air may be released, and the leakage current of the product to the ground, especially in high-altitude and thin air areas, is more likely to occur, which can affect the accuracy of the measurement of ground leakage current. Measures such as increasing the diameter of the wire, reducing the tip or increasing corona shielding, shortening the wire, and increasing the distance from the ground can reduce the impact on the measurement results.2. The influence of air humidity on surface leakage currentWhen the air humidity is high, the surface leakage current is much greater than the volume leakage current. The dirt on the surface of the tested product is prone to moisture absorption, increasing surface leakage current. The
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Application scope of air drying generator
2024-09-03Dry air generator is a very important gas manufacturing equipment in industrial production. It uses non thermal regeneration to adsorb compressed air and absorb moisture from the gas, thereby obtaining a lower dew point temperature, dry and clean gas purification equipment. Equipment suitable for users who obtain dew points below -23 ℃. It uses activated alumina with a pore size similar to that of water molecules as the adsorbent, and adopts the internationally advanced pressure swing adsorption principle. When adsorbed at room temperature, the partial pressure of water molecules in the air is greater than that in the adsorbent.It enters the adsorbent, condenses into water droplets on the surface of the adsorbent, releases condensation heat, and is stored in the upper part of the adsorption tower. During regeneration, about 15% of the dry air enters the regeneration cylinder through a needle valve at normal pressure, allowing water molecules in the adsorbent to escape. The heat stored
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Reasons and solutions for lubricating oil entering emulsification
2024-09-03The presence of moisture and vigorous stirring are the main reasons for oil emulsification. Oil and water are incompatible, as oil has a lower density than water. When oil and water are mixed, under the action of temperature, vibration, pressure, etc., they wrap around each other to form countless tiny separation surfaces, which appear white under the refraction of light. When observed with the naked eye, it appears milky white.Lubricating oil must have three necessary conditions to form lotion:1. There must be two immiscible (or partially miscible) liquids;2. There should be emulsifiers (surfactants that can reduce interfacial tension) in the two mixed liquids;3. Lotion can only be formed with energy, such as strong mixing, circulation and flow. Moisture, vigorous stirring, and emulsifiers can all cause lubricant emulsification.Emulsified white lubricating oil can be demulsified and dehydrated through a vacuum oil filter. The water separation device of the oil filtration equipment use
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