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Common troubleshooting of series resonance test device
2024-12-27The series resonance under UHV power can help many power workers conduct various power tests more conveniently.1. The fan cannot start:Phenomenon: After emergency stop, fault protection, and mismatch protection, the "fault reset" is not pressed;Reason: High internal temperature, thermal protection of power components;Exclusion method: Turn off the power supply of the instrument, let it stand for about 30 minutes, turn on the power again, press the "Reset" button on the instrument panel, and then restart the instrument.If the fan still cannot be started, please contact our company. The instrument cannot be disassembled!2. Automatic tuning cannot be completed, resonance point cannot be found:Phenomenon: The tuning curve is completely a straight line, and after tuning is completed, the instrument prompts that there is no resonance pointReason: Poor grounding of the circuit, incorrect wiring of the test circuit, and an open circuit in one of the devicesExclusion method: Check the reliabili
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What is a grounding resistance tester?
2024-12-26The grounding resistance tester under UHV power can help many power workers conduct various power tests more conveniently.What is a grounding resistance tester?The resistance between the grounding electrode and the earth is usually referred to as the grounding resistance. More precisely, grounding resistance is the sum of the resistance of the grounding conductor, the contact resistance between the grounding conductor and the earth, and the earth's resistance. The difference between grounding resistance and ordinary resistance is that it has the following special characteristics:• Polarization effectDue to the fact that the behavior of the earth is similar to that of an electrolyte, it has a polarizing effect, and direct current generates an electromotive force in the opposite direction, making it impossible to measure accurately. Therefore, grounding resistance is usually measured using square or sine waves with frequencies ranging from tens of hertz to 1 kHz.• Special measurement
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Why does the wave generator of the cable fault locator use audio instead of other frequencies?
2024-12-25The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.Why does the wave generator of the cable fault locator use audio instead of other frequencies?There are several reasons for using relatively low frequencies.Most cable analyzers use long cables, which may be kilometers or longer. At high frequencies, the attenuation becomes worse with distance. If you want to use pulses with frequency components in the 100MHz range, on most cables, you will not get any significant reflections exceeding a few hundred feet.Other reasons are that it is cheaper, easier to build, and can use less electricity.There is no reason to use a frequency higher than that required to provide the required information on the cable. For cable testers, you would like to know the length and approximate location of the fault. If you want to find the fault within one meter, you need megahertz data. If you only need to know the frequency within 10 meters, you can
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Guidelines for Karl Fischer titration method for moisture determination
2024-12-25The trace moisture analyzer under UHV power can help many power workers conduct various power tests more conveniently.Karl Fischer titration method for determining moisture contentprinciple:The Karl Fischer titration method is used as a reference method for many substances and is a chemical analysis method based on the oxidation of sulfur dioxide by iodine in methanol hydroxide solution. In principle, the following chemical reactions will occur:H 2 O + I 2 + SO 2 + CH 3 OH + 3RN -> [RNH]SO 4 CH 3 + 2[RNH]ITitration can be carried out by volumetric or potentiometric methods.In the volumetric method, add Karl Fischer solution containing iodine until the first trace of excess iodine appears. The amount of iodine converted is determined by the volume of the burette containing iodine Karl Fischer solution.In the Coulombic method, the iodine involved in the reaction is directly generated in the titration cell through the electrochemical oxidation of iodide, until trace amounts of unreacted i
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Karl Fischer test method for moisture detection
2024-12-24The trace moisture analyzer under UHV power can help many power workers conduct various power tests more conveniently.Karl Fischer titration (KF) is a technique for determining moisture content. This is a process based on the reaction between iodine and water. The KF method is one of the few techniques that can measure water content without being affected by other volatile substances. The KF titration device can measure free water and bound water, such as surface water on crystals or water inside crystals. This method is applicable to a wide concentration range from 5 ppm to 100% and provides reproducible and accurate results. Our equipment can effectively test various types of solid or liquid samples. The sample size can vary, typically between 0.5-5 grams, depending on the water content in the sample. There are two methods used to perform the Karl Fischer test, the volumetric method and the Coulomb method.Volumetric titration methodVolume titration is used in the range of moisture co
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Detailed explanation of the advantages of series resonance
2024-12-20The series resonance under UHV power can help many power workers conduct various power tests more conveniently.The development of the power industry now also provides us with a lot of convenience in our lives, especially in providing more electricity, which can be done better in certain aspects. The series resonance test device that people are familiar with now can also appear in people's sight, and because such a device can have many advantages, it can be widely used in various industries.If we understand the advantages of series resonant devices now, we will find several major advantages. The first major advantage is that the required power capacity can be reduced. This experimental device utilizes resonance between reactors and capacitors to obtain voltage and current. Therefore, in the entire system, the power supply only consumes a part of what the system needs, thus reducing power consumption. The second major advantage is that the weight and volume of the equipment have been
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Karl Fischer titration method for water content——Used for measuring moisture content
2024-12-19The trace moisture analyzer under UHV power can help many power workers conduct various power tests more conveniently.Use Karl Fischer titration to analyze the water content of oil samples. This analysis program is particularly useful for detecting high moisture content and trace moisture content. This process was invented by a German chemist named Karl Fischer in 1935.The testing process involves a chemical reaction between water and iodine in the reagent. Iodine is distributed in small amounts into the sample until the reaction endpoint is reached. The amount of iodine used in the reaction is directly proportional to the amount of water in the sample. The following reaction occurs (in the presence of a solvent mixture):I 2 + 2 H 2 O + SO 2 → 2 HI + H 2 SO 4Karl Fischer titration is very accurate and can provide results from 1ppm to 100%. Another significant advantage is that, unlike traditional loss of weight (LOD) drying methods, this process is not adversely affected by the pre
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Current transformer malfunction issue
2024-12-19The specialized production of current transformer testers for UHV power can help many power workers conduct various power tests more conveniently.1) The insulation layer of current transformers is very thick, and some insulation layers are loosely wrapped with wrinkles between them. In addition, poor vacuum treatment, incomplete immersion, and the formation of gas containing cavities can easily cause partial discharge faults.2) The size and arrangement of the capacitive screen do not meet the design requirements, and even the discharge capacity of the capacitive screen is low. The capacitive board is not smooth and even misaligned or broken, which damages the voltage equalization characteristics. Therefore, when the electric field strength along the local solid insulation surface reaches a certain value, it will cause partial discharge.The direct consequence of the partial discharge mentioned above is the cracking of the insulating oil, which generates a large amount of x wax between t
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How to protect and maintain the open flash point tester?
2024-12-18The open flash point tester under UHV power can help many power workers conduct various power tests more conveniently.In today's high-level scientific research, the data requirements for the research results are very precise, which has raised the demand for open flash point measuring instruments. They play a huge role in the innovation of common sense and skills. We cannot deny that open flash point measuring instruments are playing an increasingly important role, especially in some high-precision skill fields.The open flash point tester is an important instrument for exploring sustainable development and an increasingly indispensable device in scientific development. Nowadays, the open flash point tester has appeared as a key equipment in front of the world. Regarding the open flash point tester, two identical documents have been issued to accurately standardize the Cleveland Open Cup Method and the Binsky Martin Silent Cup Method as their calibration methods.To determine whether
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Wiring method and testing steps for portable hipot tester
2024-12-18The portable hipot tester under UHV power company can help many power workers conduct various power tests more conveniently.Wiring method and testing steps for portable hipot testerThe so-called portable hipot tester can be called an electrical insulation strength tester, dielectric strength tester, etc. according to its function. Its working principle is to apply a voltage higher than the normal operating voltage to the insulation of the tested equipment, and maintain it for a certain period of time. Within the specified time, the voltage applied to it will only generate a small leakage current, resulting in better insulation. The testing system consists of three modules: a program controlled power module, a signal acquisition and conditioning module, and a computer control system. Choose two indicators for the voltage tester: high output voltage value and high alarm current value.Wiring method for voltage tester:1. Check and confirm that the main power switch of the voltage tester is
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Advantages of using series resonant components
2024-12-17The series resonance under UHV power can help many power workers conduct various power tests more conveniently.The frequency conversion resonance test device utilizes the principle of reactive power compensation, and only requires a small capacity and low voltage test power supply to successfully complete the withstand voltage test of generators, cables, and GIS composite electrical equipment. At the same time, the testing device can also be used for on-site testing of transformers, current transformers, voltage transformers, etc. This testing method is safe and reliable, and can effectively detect electrical equipment with insulation defects.1. Principle of Frequency Conversion Resonance TestThe principle of frequency conversion resonance test is to use the equivalent capacitance of the combined equipment and a high-voltage reactor with known inductance to form a series circuit, and adjust the frequency of the test power supply through the frequency conversion power supply to achieve
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Precautions for Micro Moisture Analyzer
2024-12-16The trace moisture analyzer under UHV power can help many power workers conduct various power tests more conveniently.(1) During normal measurement, the reagent of the trace moisture analyzer can react with not less than 1.5g of water. If the measurement time is too long, the sensitivity of the reagent will decrease and a new electrolyte should be replaced.(2) If the electrolyte in the cathode chamber is contaminated by strong bubbles or electrolyte during the electrolysis process, it will increase the blank current and reduce the linearity of the measurement. Meanwhile, the time to reach the finish line will also be extended. In this case, the electrolyte should be replaced as soon as possible.(3) When the electrolysis time exceeds half an hour, the instrument becomes unstable. At this point, stirring should be stopped to determine if there is significant brown iodine production under the platinum mesh of the electrolytic electrode. If there is no or little iodine, the electrolyte sho
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Introduction to Series Resonance Knowledge
2024-12-16The series resonance under UHV power can help many power workers conduct various power tests more conveniently.The series resonance test device is a series resonance test device that uses tuned inductance and load capacitance to generate power frequency series resonance and obtain power frequency test voltage. Series resonance consists of an isolation transformer, a frequency and voltage regulating power supply, an excitation transformer, a reactor, and a capacitive voltage divider. The capacitor and reactor of the test sample form a series resonant connection; The voltage divider is connected in parallel to the test sample to measure the resonant voltage on the test sample and provide an overvoltage protection signal; The frequency modulation power output is coupled to the series resonant circuit through an excitation transformer, providing excitation power for series resonance.working principleA device that uses tuned inductors and load capacitors to generate power frequency series r
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What are the tips for using a cable fault tester?
2024-12-13The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.Some techniques for cable fault location: Cable faults occur with the laying of cables, and with different cable laying methods, cable fault location becomes increasingly difficult. Among them, the open application mode for bridge, tunnel, and trench positioning search is relatively simple, while the direct buried mode positioning search is the most difficult. When the nature of the fault is relatively simple, a dedicated cable fault locator device can be used to locate the fault within tens of minutes. When the fault is special, it usually takes 4-5 days or even longer to locate the fault.When using the echo method to locate cable faults, sometimes by transferring the fault phase and wiring method, complex faults are often transformed into simple faults and the fault location is quickly determined. The procurement time for on-site line repair is of great significance to the
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Common problems and solutions of circuit breaker tester
2024-12-13The circuit breaker tester under UHV power can help many power workers conduct various power tests more conveniently.1. Check if the working power supply of the instrument has DC outputUse a multimeter to check the voltage of the working power supply provided by the instrument. If the voltage output is normal, perform other checks; If there is no voltage output, then:(1) The fuse on the operation control line is burnt out or the control line is damaged.Solution: Replace the fuse or reconnect the control wire.(2) The internal power supply of the instrument is damaged.Solution: Use the on-site switchgear to operate the power supply, using the "external triggering" method. At the same time, notify the purchasing equipment company to carry out repairs or provide backup instruments.2. The switch has a protective lock (such as SIEMENS/ABB)Solution: ① Conduct closing/opening tests using the internal power supply of the instrument. The lock must be unlocked, and on-site technicians or manufact
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Two main cable fault location methods and their working principles
2024-12-12The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.Before locating faults in underground cables, it is necessary to know the route of the cable. How to locate the fault if you do not know where the cable is? Sometimes, you may find a cable route map in the document (which is why every job requires a good document), but when you don't have a cable route map, you need to find and track it. Locating underground cables is not only necessary for discovering faults, but also for any possible excavation near the cable route. This article will explain the types of underground cable fault locators and their working methods.Basically, there are two main methods for cable positioning:Activity location: This method involves injecting specific frequency signals through a transmitter and tracking them through a receiver to locate specific lines/cables.Passive positioning: This method involves searching for unknown lines by detecting e
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Analysis of several common safety faults in HV and LV Switchgear Test Bench
2024-12-11The HV and LV Switchgear Test Bench under UHV Power can help many power workers conduct various power tests more conveniently.HV and LV Switchgear Test Bench is a very important electrical equipment in the power system. The deterioration of the operating status of switchgear is one of the reasons for power system failures. What are the causes of faults in high-voltage switchgear? Mainly occurs in insulation, conduction, and mechanical aspects.(1) Inaction or malfunctionThis type of fault is the most common fault in high-voltage switchgear, and its causes can be divided into two categories. One type is caused by mechanical faults in the operating mechanism and transmission system, manifested as mechanism jamming, component deformation, displacement or damage, loose and jammed opening and closing iron cores, loose shaft pins, tripping faults, etc. Caused by electrical control and auxiliary circuits, it manifests as poor contact of secondary wiring, loose terminals, wiring errors, mechani
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The difference between series resonance and parallel resonance
2024-12-11The series resonance under UHV power can help many power workers conduct various power tests more conveniently.Resonance is one of the most common phenomena in power systems. According to the different forms of harm caused by harmonic resonance, it can be divided into series resonance and parallel resonance. The former is prone to causing overvoltage phenomena. The latter can easily cause overcurrent injuries. Resonance can further exacerbate the distortion of voltage and current, and sometimes even cause damage to power equipment and connecting devices, leading to safety faults in the system.Series resonant deviceThe basic characteristic of a series resonant power supply system is the complex combination of inductors and components. When a node or branch of the system experiences nonlinear loads, it is easy to cause resonance in the system. When series resonance occurs, the impedance of the line is minimized, and when nonlinear loads appear at the nodes or branches of the system, the
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Reasons and prevention of partial discharge in transformers
2024-12-10The specialized production of partial discharge testers for UHV power can help many power workers conduct various power tests more conveniently.Partial discharge is mainly caused by high-voltage electrical engineering equipment such as transformers and transformers under the action of high voltage. Discharge occurs inside the insulation. For example, partial discharge only exists in the insulation area, and the insulation does not immediately pass through to form a complete breakdown or flashover, which is called partial discharge. The partial discharge is very weak and can be felt intuitively by humans. If neither the eyes nor the ears can detect it, only a sensitive partial discharge tester can detect it.The internal insulation of the transformer is subjected to the working voltage for a long time during operation, especially with the increase of voltage level, the electric field strength value of the insulation is very high. Weak insulation is prone to partial discharge. The reason
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Selection method and factors to be considered for experimental transformers
2024-12-10The professional production of high-voltage test transformers in UHV power can help many power workers conduct various power tests more conveniently.When selecting a test transformer, the following aspects should be considered:1) Test voltage. According to the requirements of the tested product, first select a suitable voltage test transformer, so that the rated voltage Un on the high voltage side of the test transformer is higher than the test voltage Us of the tested product. Secondly, check whether the low voltage side voltage required by the test transformer can match the on-site power supply voltage and voltage regulator.2) Test the current. The rated output current In of the test transformer should be greater than the current Is required by the tested product, that is, In>Is. The current required for testing a product can be estimated based on its capacitance, Is=UswCx, where Cx includes the capacitance of the test product and additional capacitance.3) Testing ability. Based on t
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