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What are the characteristics of resonant circuits?
2024-11-05The series resonance under UHV power can help many power workers conduct various power tests more conveniently.When a series circuit resonates in practical applications, it is necessary to consider both the selectivity of the circuit and the ability of the circuit to allow signals to pass through within a certain range. So what exactly is a series resonant circuit? What are the characteristics of a series resonant circuit? Below is an analysis for everyone.1. Series resonant circuitIn an AC circuit with resistor R, inductor L, and capacitor C components, the voltage at both ends of the circuit is generally different in phase from the current in it. If the parameters or power frequency of circuit components (L or C) are adjusted, they can be made to have the same phase, and the entire circuit appears purely resistive. When a circuit reaches this state, it is called resonance. In the resonant state, the total impedance of the circuit reaches or approximates its maximum value. There are t
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Sampling accuracy of Karl Fischer moisture analyzer
2024-11-04The trace moisture analyzer under UHV power can help many power workers conduct various power tests more conveniently.The Karl Fischer moisture analyzer is suitable for determining the moisture content in various organic and inorganic substances. What aspects should be paid attention to when using?1、 Testing of organic and inorganic compoundsThe Karl Fischer method is suitable for determining the water content in many inorganic and organic compounds.Due to the difference in properties of compounds, they can be divided into two categories: those that can be directly measured and those that cannot. Therefore, it is requested that analysts first consider which category a certain compound belongs to when determining its water content. If it is the latter and direct determination is chosen, significant measurement errors will occur or the basis cannot be determined.If water in compounds that cannot be directly measured is to be measured, appropriate methods must be used to eliminate various
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Scope of requirements for microcomputer relay protection tester
2024-11-04The relay protection tester under UHV power can help many power workers conduct various power tests more conveniently.Microcomputer relay protection has been widely used in various fields such as line protection, differential protection, primary transformer, excitation control, etc. Integrated automation of substations has become mainstream. Relay protection tester is an important testing tool for ensuring the safe and reliable operation of power systems. With the rapid development of computer technology, microelectronics technology, and power electronics technology, continuously introducing the latest technological achievements of new high-performance relay protection test devices is an inevitable trend of technological progress.The full name of the microcomputer relay protection tester is: microcomputer relay protection calibrator, microcomputer continuous protection, relay protection tester, three-phase relay protection tester, emergency tester, three-phase success tester, three-pha
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The function of petroleum acid value tester
2024-11-01The acid value tester under UHV power can help many power workers conduct various power tests more conveniently.The fully automatic acid value analyzer for petroleum products (environmentally friendly) is a specialized instrument designed for laboratories. It has the advantages of small size, light weight, high accuracy, easy operation, environmental protection, and is suitable for use in harsh outdoor environments. The instrument adopts high-performance microprocessors and HDD new technology, which can analyze several samples simultaneously, automatically rotate the sample cup, automatically titrate the sample, automatically determine the endpoint of the sample, automatically print the test results, and avoid contact between staff and chemical reagents. This instrument is suitable for various laboratories such as military, power, and petroleum.① Based on the acidity content, the content of acidic substances in petroleum products can be determined. Generally speaking, the higher the ac
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How to use a grounding resistance tester?
2024-10-31The grounding resistance tester under UHV power can help many power workers conduct various power tests more conveniently.1. Two line methodCondition: There must be a known grounding, such as PEN, and the measured result must be a known resistance. If it is known that it is much smaller than the measured resistance, the measurement result can be taken as the result of the tested grounding.Suitable for areas with dense buildings or cement.Wiring: Connect E+ES and H+S to a known ground.2. Three line methodCondition: There must be two grounding rods: one auxiliary ground and one detection electrode. The distance between each grounding electrode shall not be less than 20 meters. The principle is to add a current between the auxiliary and measurement, measure the voltage drop between the measured ground and the detection electrode, and the measurement result includes the resistance of the cable itself.Suitable for: ground grounding, construction site grounding, and lightning ball type light
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The total resistance of the series resonance test device
2024-10-31The series resonance under UHV power can help many power workers conduct various power tests more conveniently.The reason why the resistance is not equal to the power supply voltage during resonance is that the voltage on the resistance during resonance is the sum of the power supply voltage and the voltage of the charging and discharging capacitors. So, resistance voltage=power supply voltage+capacitor voltage, not equal to power supply voltage. When a series resonant circuit resonates, the total impedance of the series resonant circuit is equal to the resistance, and the total resistance of the series resonant circuit is equal to the total voltage and the voltage across the resistance. At this time, there is voltage on both the capacitor and inductor, and the voltage on the inductor is equal to the voltage on the capacitor, but the voltage direction is opposite. Be careful when operating, and do not mistakenly believe that there is no voltage on capacitors and inductors, which may ca
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Is a megohmmeter harmful to the human body?
2024-10-30The megohmmeter under UHV power can help many power workers conduct various power tests more conveniently.Is a megohmmeter harmful to the human body?A megohmmeter, also known as an insulation resistance tester The main function of a megohmmeter is to measure resistors with higher resistance values. Generally used to measure insulation resistance, such as the insulation performance of electrical equipment such as motors, cables, materials, etc. A megohmmeter is an insulation resistance tester designed specifically for measuring high resistance. Measuring larger resistors requires a higher input voltage. The larger the measured resistance value, the higher the required voltage. According to U=IR, when the current is constant, the higher the measured insulation resistance, the higher the required voltage. A megohmmeter can generate DC negative high voltage through circuit boosting. Usually, a megohmmeter can output 250V, 500V, 1000V, 2500V, 5000V (5kV), 10000V (10kV), 15000V (10kV), 20000
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Three schemes for checking whether a cable is live using a live cable identification device
2024-10-29The live cable identification device under UHV power can help many power workers conduct various power tests more conveniently.Nowadays, the development of the power system has become increasingly complete, and the demand for cables in the market is also constantly increasing. Today, the editor will mainly talk about three solutions for using a live cable identification device to determine whether a cable is live, including the path finding and identification of live cables, as well as the path finding and identification of cables operating at 50Hz. If you are also interested in this area, continue reading.1、 Can the problem of identifying live cables be solved?The answer is affirmative. Routing and identification of live cables, as well as routing and identification of cables operating at 50Hz.These are the three solutions for determining whether a cable is live using a live cable identification device.Routing of live cables: By clamping the transmitter onto the cable with coupling cl
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The significance of acid value detection instrument measurement
2024-10-29The acid value tester under UHV power can help many power workers conduct various power tests more conveniently.The fully automatic acid value analyzer for petroleum products (environmentally friendly) is a specialized instrument designed for laboratories. It has the advantages of small size, light weight, high accuracy, easy operation, environmental protection, and is suitable for use in harsh outdoor environments. The instrument adopts high-performance microprocessors and HDD new technology, which can analyze several samples simultaneously, automatically rotate the sample cup, automatically titrate the sample, automatically determine the endpoint of the sample, automatically print the test results, and avoid contact between staff and chemical reagents. This instrument is suitable for various laboratories such as military, power, and petroleum.Based on the acid value, the amount of acidic substances contained in the oil can be determined.2. Due to the influence of oxygen, temperature,
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Characteristics of High Voltage Switch Mechanical Characteristics Tester
2024-10-28The circuit breaker tester under UHV power can help many power workers conduct various power tests more conveniently.Suitable for mechanical characteristic testing of various SF6 switches, GIS composite electrical appliances, vacuum switches, and oil circuit switches produced domestically and internationally.Super strong anti-interference ability, able to easily and accurately test and measure even when the bypass busbar of a 500kV substation is live.Universal speed sensor (optional), linear walking speed sensor, speed sensor, easy and simple installation.High voltage switch mechanical characteristic testerAfter one switch operation, obtain all data and corresponding waveform diagrams for the mechanical characteristics test of the switch.The host can store on-site test data and use the real-time clock inside the machine to archive and save the test date and time.Host large screen, wide temperature range, direct view, background light LCD, full Chinese data and image display, LCD contra
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Selection of series resonant devices
2024-10-25The series resonance under UHV power can help many power workers conduct various power tests more conveniently.The application range of variable frequency series resonant reactance instruments is very wide, and there are many types of products on the market. Many customers do not know how to choose. In fact, the selection of reactance instruments is not complicated. We only need to grasp the key points of selection, and we can quickly choose the suitable and desirable reactance instrument.Choosing a variable frequency series resonant reactance instrument requires selecting from three elements, namely current flow value, voltage drop value, and inductance value. These three values are important criteria for us to choose products. The first factor is to choose a fixed AC current value, which focuses on heat generation. The long-term operating current value of the reactance instrument should be set from this aspect, and sufficient high harmonic component values should be considered. The a
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Preventive measures for cable faults
2024-10-25The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.1、 Reasons for moisture or water ingress in polyethylene insulated cables.Moisture or moisture enters the insulation layer of cross-linked polyethylene insulated power cables during laying, installation, and operation. There are mainly the following situations1. The cable end cover is not tightly sealed, or the cable is damaged by external forces during transportation and laying.During the transportation or laying of cables, the cable protective layer is damaged by external forces.3. Cable insulation breakdown damages the cable sheath during cable testing or operation.4. Cable accessories (especially intermediate joints directly buried) are not tightly sealed. Once moisture or moisture enters the cable insulation from the end of the cable or the outer protective layer of the cable, it may penetrate longitudinally through the copper wire shielding gap or conductor gap outside
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The difference between acousto-optic high-voltage tester and luminescent high-voltage tester
2024-10-24The voltage tester under the UHV power can help many power workers conduct various power tests more conveniently.High voltage voltage voltage tester is a specialized tool used by power companies such as power plants and substations to detect whether electrical equipment is live. On site operation has sound and light alarms, which are safe and reliable. Whether it's day or night, indoor substations or outdoor overhead lines, we can serve you correctly and reliably. It is an essential safety equipment for the electrical department of the power system and industrial and mining enterprises. High voltage voltage voltage testers are mainly used to detect whether high-voltage overhead lines, cable lines, and high-voltage electrical equipment are live. The main types of high-voltage voltage testers include luminous high-voltage testers, acousto-optic high-voltage testers, and high-voltage electromagnetic induction rotating testers.1. Luminous high-voltage voltage testerThe luminous high-vo
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Questions and Answers on Insulation Resistance Testing
2024-10-23The insulation resistance tester under UHV power can help many power workers conduct various power tests more conveniently.Insulation resistance testing is one of the most common testing techniques applicable to various electrical equipment, so we do not apologize for taking this opportunity to study some basic questions related to this important topic that are often asked.Q: What is the reason for conducting insulation resistance testing?Answer: These types of tests are usually fast and relatively easy to perform, and only require commonly used testing equipment. However, it can provide valuable early warning for potential weaknesses in insulation, which, if not taken seriously, may ultimately lead to costly and destructive in use failures.Q: What is the difference between polarization index (PI) testing and ordinary insulation testing?Answer: In the polarization index test, the insulation resistance of the test object is continuously measured for 10 minutes. Then the tester will auto
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Details of High Voltage Switch Dynamic Characteristics Tester
2024-10-23The circuit breaker tester under UHV power can help many power workers conduct various power tests more conveniently.The high-voltage switch dynamic characteristic tester is designed based on the latest "High Voltage AC Circuit Breaker" GB1984-2003, and refers to the power industry standard "General Technical Conditions for High Voltage Test Equipment" Part 3 DL/t846.3-2004 High Voltage Switch Comprehensive Tester as the design basis. It provides convenience for the dynamic analysis of various circuit breakers and can accurately measure the mechanical and dynamic characteristic parameters of various voltage low oil, multi oil, vacuum, and sulfur hexafluoride high-voltage circuit breakers. For users who are using the high-voltage switch dynamic characteristic tester for the first time, Wuhan Hezhong Electric reminds them of the following testing rules:Check and familiarize yourself with the operating instructions attached to the high-voltage switch dynamic characteristic testerIt is ver
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A Comprehensive Introduction to Insulation Oil Dielectric Loss Testing
2024-10-22The insulation oil dielectric loss tester under UHV power can help many power workers conduct various power tests more conveniently.1、 Noun Explanation:capacitanceAlso known as "capacitance", it refers to the amount of charge stored at a given potential difference, denoted as C, and the international unit is Farad (F). Generally speaking, charges move under force in an electric field. When there is a medium between conductors, it hinders the movement of charges and causes them to accumulate on the conductors, resulting in the accumulation and storage of charges. The amount of stored charge is called capacitance.(Relative) permittivityThe relative permittivity of an insulating material is the ratio of the capacitance C around and between the two electrodes of a capacitor filled with the insulating material to the capacitance q of the same electrode structure in vacuum.Replacing q with the capacitance of the electrode in air has sufficient accuracy for measuring relative permittivity.Die
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Classification and application of different types of test transformers
2024-10-21The high-voltage test transformers under UHV Power can help many power workers conduct various power tests more conveniently.This test transformer is widely used in the power industry and is highly welcomed by power workers. At present, test transformers are divided into several types: dry-type test transformers, oil immersed test transformers, and gas filled test transformers. Different types of test transformers are different.The dry-type test transformer is made of coil epoxy resin vacuum casting and is an important equipment for insulation strength and withstand voltage testing. This test transformer is suitable for on-site testing of insulation performance of various electrical equipment in power systems and power users. The coil winding and CD type iron core adopt a new technology of epoxy resin vacuum casting.Compared with oil immersed test transformers of the same capacity and voltage, dry-type test transformers reduce leakage magnetism, improve insulation strength and moisture
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Calculation formula for series resonance
2024-10-21The series resonance under UHV power can help many power workers conduct various power tests more conveniently.For ideal L and C components, when series resonance occurs, the voltage on the L and C components is equal in magnitude and opposite in direction, and the total voltage is equal to 0 (resonant impedance is zero). When parallel resonance occurs, the current in the L and C components is equal in magnitude and opposite in direction, and the total current is equal to 0 (the resonant impedance is infinite).Calculation formula for series resonanceWhen the series resonance occurs, the imaginary part of the impedance of the circuit is equal to 0, Z=R+jX, X=0, Z=R, so I=U/Z=U/R.1. Resonance definition: The energy of components L and C in a circuit is equal. When energy is released by one of the reactive components in the circuit, and the other reactive component must absorb the same energy, an energy pulsation will occur between these two reactive components.2. To generate resonance in
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The principle of batteries and the principle of battery charging and discharging testers
2024-10-18The battery charging and discharging tester under the UHV power company can help many power workers conduct various power tests more conveniently.In chemical batteries, chemical energy is directly converted into electrical energy. Depending on the internal characteristics of the battery, spontaneous oxidation, reduction, and other reactions occur on two electrodes. The negative electrode active material is composed of potential reducing agents and stable reducing agents such as zinc, cadmium, lead, etc. in the electrolyte.The positive electrode active material is composed of a potential and a stable oxidant stabilized in the electrolyte, such as metal oxides, oxygen or air, halogens and their salts, oxygen-containing acids and their salts, etc Electrolytes are materials with good ionic conductivity, such as acids, bases, salts, organic or inorganic non-aqueous solutions, molten salts, or solid electrolytes.When the external circuit is turned off, although there is a potential differenc
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A Comprehensive Introduction to Series Resonance
2024-10-17The series resonance under UHV power can help many power workers conduct various power tests more conveniently.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 exhibits pure resistive behavior. This phenomenon is called series resonance.Series resonance is divided into frequency modulation and induction modulation. It is generally composed of a variable frequency power supply, excitation transformer, reactor, and 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.Series resonance, also known as series resonance transformer, variable frequency resonance, variable frequency series reson
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