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Cable fault tester accurately locates cable faults
2025-04-30The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.The power cable fault tester consists of three main parts: the power cable fault tester host, the cable fault locator, and the cable identifier. The host of the cable fault tester is used to measure the nature of cable faults, the total length and approximate location of the cable fault point at the testing end. The cable fault indication device determines the location of the cable fault point based on the approximate position of the cable fault tester host, in order to identify the cable fault point.For buried cables with unknown directions, a path meter is used to determine the underground direction of the cable. The basic method for testing power cable faults is to apply high-voltage pulses to the faulty power cable, causing a fault at the fault point of the cable. At the same time as the cable breaks through the breakdown point, electromagnetic waves are generated and so
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How to safely use the dielectric strength of insulating oil?
2025-04-30The specialized production of insulation oil dielectric strength tester for UHV power can help many power workers conduct various power tests more conveniently.1. Use a suitable power cord. Only use dedicated and compatible power cords.2. Connect and disconnect correctly. When connecting the test wire to the live terminal, do not connect or disconnect the test wire at will.3. Pay attention to the rated values of all terminals. To prevent fire or electric shock hazards, please pay attention to all ratings and markings. Before continuing with the connection, please read the instruction manual for more information about ratings.4. Use appropriate fuses. Only use fuses that meet the specified type and rating. Avoid contact with bare circuits and live metals. Do not touch exposed contacts and components when there is electricity.5. Do not operate in damp environments.6. To ensure operational safety, the high-voltage chamber of the instrument adopts a safety protection switch to prevent the
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Analysis of the Reasons for Unbalanced DC Resistance Testing of Transformers
2025-04-29The DC resistance tester under UHV power can help many power workers conduct various power tests more conveniently.In the DC resistance test of transformers, the DC resistance value of the winding will be unbalanced. The reasons can be divided into three situations: human factors, winding structure and material problems, and transformer defects.1. Human factors mainly include incorrect instrument selection, incorrect testing methods, and inadequate key testing points. These problems are mainly solved by improving the quality of personnel themselves.Unreasonable winding structure design and unqualified conductor materials can also lead to excessive DC resistance imbalance.2. Poor connection of internal structural components of transformerIf the winding leads are not well connected to the conductive rod or tap changer, or if the bushing cap has poor contact with the conductive rod, it will exceed the unbalanced DC resistance of the transformer. In this case, the DC resistance values of o
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What is the purpose of partial discharge test for transformers?
2025-04-29The specialized production of partial discharge testers for UHV power can help many power workers conduct various power tests more conveniently.Power transformers mainly use oil paper barrier insulation, which is composed of electrical paper and insulating oil. Due to the complex structure and uneven insulation of large transformers. When there are internal defects such as improper design, high local field strength, poor process or external factors, partial discharge will inevitably occur in transformers and gradually develop, ultimately causing transformer damage. Partial discharge inside power transformers mainly occurs in the following situations:(1) The oil paper isolation insulation in the middle of the winding breaks through the oil passage;(2) Fault in the oil passage at the end of the winding;(3) The oil gap between the insulated wire and the electrical paper (lead insulation, lap insulation, phase insulation) is broken down;(4) The vertical insulation oil passage between coils
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What is the principle of series excitation test transformer?
2025-04-28The AC series resonance test system under UHV power can help many power workers conduct various power tests more conveniently.The difference between a series excited test transformer and a regular test transformer is that more than two test transformers are connected in series for power on testing. Series testing of two or more test transformers is more flexible than testing a single transformer. This is because there are different voltage levels, and with the addition of test transformers, the voltage level required for the test can be more flexibly selected. So what is the principle of the series excitation test transformer? This article introduces to you.The principle of the series excitation test transformer is that, in addition to the high-voltage primary test transformer, the excitation winding is connected in series in the high-voltage winding. The parameters of this set of windings are consistent with the primary winding of the transformer tested later. Power the primary windin
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What are the specific functions of a power quality analyzer?
2025-04-27The power quality analyzer under UHV power can help many power workers conduct various power tests more conveniently.The power quality analyzer adopts advanced data acquisition and DSP technology, as well as on-site microcomputer display, storage, management, and communication technology, to achieve real-time measurement and storage of five power quality indicators and various commonly used electrical parameters Its main functions are as follows:1、 Test analysis function1. Basic parameter measurement: including three-phase voltage, current, power, power factor, etc2. Grid frequency3. Voltage (current) fundamental wave and harmonic amplitude, phase, power, impedance;4. Voltage deviation5. Voltage fluctuations and flicker, frequency spectrum analysis of amplitude modulation waveforms;6. Three phase voltage imbalance;2、 Data management functionStorage, retrieval, and remote transmission of data files such as test analysis results and statistical results.3、 Graphic functionOutput various v
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Under what circumstances will a gas chromatograph be used?
2025-04-27The oil chromatography analyzer under UHV power can help many power workers conduct various power tests more conveniently.In my daily work, I often hear the sound of a gas chromatograph. 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. Organic solvents such as acetone and methanol can be used for timely cleaning, and the
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Karl Fischer analysis for determining water content
2025-04-25The trace moisture analyzer under UHV power can help many power workers conduct various power tests more conveniently.Karl Fischer titration (KF) is a method in analytical chemistry that uses Coulombic, volumetric, or oven titration to determine trace levels of water content in a sample. The Karl Fischer titration method is very popular because it has multiple practical advantages compared to other moisture determination methods, such as accuracy, speed, and selectivity. KF has selectivity towards water because the titration reaction itself consumes water. On the contrary, the measurement of quality loss during drying will detect the loss of any volatile substances. KF has high precision and accuracy, typically within 1% of available water, such as 3.00% displayed as 2.97-3.03%. KF response is linear and usually takes only a few minutes to complete. Therefore, using a calibrated 1% water standard for single point calibration is sufficient, and there is no need to calibrate the curve.
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Common faults and prevention of zinc oxide lightning arrester
2025-04-25The zinc oxide lightning arrester tester under UHV power can help many power workers conduct various power tests more conveniently.A lightning arrester is a lightning protection device used to prevent lightning waves from invading substations along power lines and damaging electrical equipment. Under normal operating voltage, the gap of the lightning arrester will not be broken down, and the leakage current flowing through the lightning arrester is very small. When lightning waves strike, the gap between the lightning arrester will be quickly broken down by the charged tester of the zinc oxide lightning arrester and discharged to the ground, limiting the overvoltage value of the protected equipment and playing a protective role.Common faults of the live testing instrument for zinc oxide lightning arrester include:1. Poor sealing performance.The poor sealing of lightning arresters is mainly caused by production processes. Some manufacturers use substandard materials and poor quality por
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What are the advantages and disadvantages of a trace moisture analyzer?
2025-04-24The trace moisture analyzer under UHV power can help many power workers conduct various power tests more conveniently.Advantages of Karl Fischer titration (also known as trace moisture analyzer)Due to the fact that KF titration is based on chemical reactions that depend on the presence of water, it has extremely high accuracy.The specificity of moisture determination is different from other methods, such as heat induced moisture loss and sample weight reduction drying loss, as it does not detect the loss of other volatile substances.The determination range for parts per million (ppm) ranges from 0.001 to 100%, or from 100% to 1, with smaller percentages up to 1%, suitable for Coulombic KF titration, while samples with water content exceeding 2% are measured by volumetric method (suitable for samples with 0.1 to 500 milligrams of water).The Coulomb method avoids the need for titration determination, therefore it is an absolute method, and the amount of current consumed is directly relat
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What are the usage methods and working principles of a clamp shaped gauge?
2025-04-23The clamp type grounding resistance tester under UHV power can help many power workers conduct various power tests more conveniently.Clamp on ammeter is divided into high voltage and low voltage, used to directly measure the current in the line without disconnecting the line. The usage method and precautions are as follows:(1) When using a high-voltage clamp ammeter, pay attention to the voltage level of the clamp ammeter. It is strictly prohibited to use a low-voltage clamp meter to measure the current of high-voltage circuits. When measuring with a high-pressure clamp gauge, it should be operated by two people. Non duty personnel should also fill out the second type of work ticket. When measuring, insulating gloves should be worn, standing on an insulating pad, and not touching other equipment to prevent short circuits or grounding.(2) When observing the time on a watch, special attention should be paid to maintaining a safe distance between the head and the live parts. The distance
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How to choose a suitable insulator tester?
2025-04-23The insulator tester under UHV power can help many power workers conduct various power tests more conveniently.At present, there are many types of insulator testers on the market, such as resistance testers, waterproof testers, flaw detectors, ash density and salt density testers, etc. So how to choose the appropriate insulator tester products?Firstly, it should be noted that ordinary insulators are divided into three categories: disc suspension insulators, composite insulators, and column insulators. Next, I will introduce three common types of insulator faults:1、 Suspended disc insulator: The common faults of this type of insulator are mainly caused by its own quality defects, lightning strikes, aging, etc., resulting in zero surface pollution, moisture and other abnormal discharges; This type of fault is generally detected using two methods: insulation resistance measurement and stepwise voltage measurement.2、 Composite insulator: The common faults of this type of insulator are main
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Method for replacing reagents in trace moisture analyzer
2025-04-22The trace moisture analyzer under UHV power can help many power workers conduct various power tests more conveniently.Method for replacing reagents in trace moisture analyzer(1) Prepare a clean filter paper and place the two drying tubes of the electrolytic cell on the filter paper. Remove the electrolyte electrode, pour out the electrolyte from the cathode chamber (electrolytic electrode), and then slowly pour out the electrolyte from the anode chamber (electrolytic cell bottle) (be careful not to pour out the stirrer).(2) Generally, it is not necessary to clean the electrolytic cell. After contamination, it must be cleaned strictly according to (3).(3) Cleaning: Electrolytic cell bottles, drying tubes, sealing plugs, and measuring electrodes can be cleaned with anhydrous methanol and other anhydrous solvents. If necessary, they can also be cleaned with water; The cathode chamber (electrolytic electrode) should not be cleaned with water as much as possible. When cleaning with water, b
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How to choose a DC resistance tester?
2025-04-22The DC resistance tester under UHV power can help many power workers conduct various power tests more conveniently.The transformer DC resistance tester is subdivided into specifications such as 1A, 3A, 5A, 10A, 20A, 40A, 50A, 100A, etc. The instrument power supply is divided into external power supply AC220V, internal power supply (battery power supply), AC and DC power supply, etc. At present, DC resistance testers with a current of 10A or higher on the market are not battery powered.When users choose a transformer DC resistance tester, they are usually not very clear about what current DC resistance tester to choose. In many cases, the selection of a DC resistance tester is unreasonable.Performance requirements, technical specifications, and characteristic analysis of transformer DC resistance tester:1. Current and voltage: In actual measurement, different test currents should be selected based on different subjects. When the current selection is too small, it will affect the measure
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What should be noted when using a trace moisture analyzer?
2025-04-21The trace moisture analyzer under UHV power can help many power workers conduct various power tests more conveniently.When we use a trace moisture analyzer, we tend to overlook some details, which can be big or small, but if we cannot control it well, it can even affect the equipment, perhaps in terms of quality. Perhaps it is for testing the accuracy of data, so whenever we need to handle details well, let's briefly introduce its usage details, hoping it can be helpful to you.1、 When using a trace moisture analyzer, the water level must be maintained.2、 When placing the rotor into the sample, it is necessary to prevent the generation of bubbles. Otherwise, the measured viscosity will decrease. The preventive measure is to tilt the rotor into the sample and then place the rotor. The rotor cannot touch the cup wall and cup bottom. Do not mark the measurement sample.3、 When measuring different samples again, it is necessary to link the cleanliness and boredom of the rotor. If there a
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What principles should be followed for oil supply and replacement of transformers?
2025-04-18Due to the long operating time of transformers, oil replenishment is inevitable, and oil changes after major equipment repairs are also common. Therefore, the principle of replacing transformer oil should be as follows:1. It is best to use the same brand of oil as the original equipment for refueling;2. Require both parties to add the same antioxidant or neither party to contain it;3. The mixed parties have good quality and performance indicators that meet the standards of working oil or new oil;4. If one of the working oil indicators approaches the limit value of the control standard, a mixing test should be conducted; If one or more indicators are not qualified, the oil should be purified or regenerated before mixing;5. New oil of the same brand can be mixed in any proportion as long as the indicators are qualified; Mixing new oil of the same brand with running oil that has already started to age or is close to the operating oil index. use;6. If different grades of new oil are mixed
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The hazards and testing methods of transformer winding deformation
2025-04-18The UHV power professional production transformer winding deformation tester can help many power workers conduct various power tests more conveniently.1、The hazards of transformer winding deformationThe deformation of transformer windings is a major hidden danger to the safe operation of transformers. The actual test results of multiple transformers show that it is difficult to detect the deformation of transformer windings in oil and insulation tests. This is a potential malfunction that is usually difficult to detect.According to the report of the committee attending the 12th International Conference on Power Grids, there have been multiple instances of insulation failure in transformer windings due to initial mechanical damage to the insulation. When a transformer is subjected to the impact of short-circuit fault current, although the winding will partially deform, it will not be immediately damaged, but there will still be certain hidden dangers. Therefore, the harm caused by windi
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Basic principles of relay protection
2025-04-17The relay protection tester under UHV power can help many power workers conduct various power tests more conveniently.The relay protection device must have the function of correctly distinguishing whether the protected component is in normal operation or has a fault, and whether it is a fault within the protection zone or outside the zone. To achieve this function, protective devices need to be constructed based on the characteristics of changes in electrical physical quantities before and after power system failures. The main characteristics of changes in power frequency electricity after a power system failure are:(1) The current increases. When a short circuit occurs, the current on the electrical equipment and transmission lines between the fault point and the power source will increase from the load current to significantly exceed the load current.(2) Voltage drops. When phase to phase short circuit and ground to ground short circuit faults occur, the phase to phase voltage or pha
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What are the hazards of series resonance to circuit systems?
2025-04-16The AC series resonance test set under UHV power can help many power workers conduct various power tests more conveniently.What is AC series resonance?In a series circuit composed of resistors, inductors, and capacitors, when the capacitive reactance XC is equal to the inductive reactance XL, i.e. XC=XL, the phase of the voltage U and current I in the circuit are the same, and the circuit is purely resistive. This phenomenon is called series resonance. When the circuit has series resonance, the impedance of the circuit is Z=√ R2+(XC-XL)/2=R. The total impedance in the circuit is the smallest, and the current will reach its maximum value. When resonance occurs, inductance equals capacitance, so the effective value of the voltage across the inductance and capacitance is equal, that is: UL = UC。 And due to their opposite phases, these two voltages cancel each other out. The effective voltage value of a capacitor or inductor is:What are the hazards of series resonance in circuit systems?In
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Fault testing of buried cable fault tester
2025-04-16The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.The buried cable fault tester adopts multiple detection methods and applies modern advanced electronic technology achievements. It adopts computer technology and microelectronics technology, and has the characteristics of high intelligence, complete functions, wide range of use, accurate testing, and convenient use.The buried cable fault tester consists of a transmitter, a receiver, an induction probe, a potential difference detector, etc. This instrument uses electromagnetic induction method to track optical cable lines and burial depth, and uses potential difference method to locate optical cable faults. Suitable for the wiring, burial depth testing, and wiring of various optical cables and cables with metal wires (wire pairs, protective layers, shielding layers), as well as the wiring of poor insulation points to the ground. It is a specialized line fault tester for posta
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