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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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The necessity of power prevention testing
2025-04-15Preventive testing focuses on "prevention" and "pre prevention". The power equipment operating in the power system needs to undergo strict testing to ensure its safe operation, thereby safeguarding the safety of users' lives and property. Therefore, preventive testing plays an important role in the power system!According to Chinese regulations, power equipment in the power system should be tested in accordance with the requirements of the People's Republic of China's power industry standard DL/T596-1996 Preventive Testing Specification for Power Equipment.The necessity of preventive testing:The power system operates a large number of power equipment, and the safe operation of power equipment is a prerequisite for ensuring the safety and reliability of power generation and supply.There may be some quality issues in the design and manufacturing process of power equipment, and damage may occur during installation and transportation, leading to potential failures. During the op
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What are the characteristics of a circuit resistance meter?
2025-04-15The circuit resistance tester under UHV power can help many power workers conduct various power tests more conveniently.1、 High currentThe circuit resistance tester adopts the latest switching power supply technology, which can continuously output high current for a long time, overcoming the disadvantage of high instantaneous current of pulse power supply, effectively breaking the oxide film of switch contacts, and obtaining good test results.2、 High stabilityIn the case of severe interference, the final data of the LCD can remain stable within ± 1 word range, with stable readings and good repeatability.3、 High precisionThe circuit resistance tester adopts bidirectional high-speed 16 bit sigma delta AD sampling and the latest digital signal processing technology, with a maximum resolution of 0.01 μ Ω. At present, it is a very stable contact resistance tester in China that can achieve a resolution of 0.01 μ Ω, and its performance exceeds that of imported high current micro ohmmeters.4、
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What issues should be noted when using a DC high-voltage generator?
2025-04-14The DC high-voltage generator under the UHV power company can help many power workers conduct various power tests more conveniently.There are several issues to be aware of when using a DC high-voltage generator:1. Please note that only professionals holding a High Voltage Test Certificate are allowed to operate and use the DC high voltage generator.2. During the use of DC high-voltage generators, it is necessary to strictly comply with the provisions of the "Electricity Safety Regulations". At the same time, add two obvious disconnect points before testing the power supply into the device. Before replacing the tested product and wiring, please ensure that both power disconnection points have been clearly disconnected.3. Before testing, the control box of the tester, the voltage doubler, and the grounding wire of the test product must be connected properly. The ground wire of the test circuit should be strictly grounded according to the equipment manual.4. The discharge of large capacit
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How to proficiently use the zinc oxide lightning arrester tester?
2025-04-11The zinc oxide lightning arrester tester under UHV power can help many power workers conduct various power tests more conveniently.The zinc oxide lightning arrester tester is a specialized instrument used to test the electrical performance of lightning arresters. This instrument is suitable for detecting the live or power-off status of lightning arresters of various voltage levels, and promptly detecting dangerous defects such as equipment insulation moisture and valve aging.This device is simple and easy to use. During the entire measurement process controlled by the industrial computer, all measured currents, resistance currents and their harmonics MOA, frequency reference voltages and their harmonics, active power and phase, actual voltage, and large screen current waveforms. The instrument adopts digital waveform analysis, and the harmonic analysis results are accurate. The digital filtering software stabilizes the interference method, accurately analyzes the basic harmonic content
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What are the technical requirements for a grounding resistance tester?
2025-04-11The grounding resistance tester under UHV power can help many power workers conduct various power tests more conveniently.The grounding resistance tester, combined with the new lightning protection grounding resistance detection standard, is carefully designed and manufactured for on-site measurement of grounding resistance, soil resistivity, grounding voltage, and AC voltage. The test current reaches 20mA, and digital and microprocessing techniques are used to measure the grounding resistance using the 4-wire method, 3-wire method, and simple 2-wire method. Introducing FFT (Fast Fourier Transform) technology and AFC (Automatic Frequency Control) technology to automatically identify interference and select measurement frequency, minimizing the impact of interference and providing more accurate grounding resistance values.It has unique anti-interference ability and environmental adaptability, with good consistency in repeated testing, ensuring high precision, stability, and reliability
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Basic Introduction of Live Cable Identification Instrument
2025-04-10The live cable identification device under UHV power can help many power workers conduct various power tests more conveniently.The live cable identification device is a flexible coil cable identification device that is convenient for on-site operation. It comes with a built-in lithium battery and can perform live cable identification work without the need for a power source. The live cable identification device is designed for both AC and DC use, and can be powered by a lithium battery or a 220V charger. It is versatile and can identify both operating and non operating cables. So, what are the basic precautions to pay attention to when using the live cable identification device?1. If there is grounding or branching in the middle of the live cable. Only the part before cable grounding or branching can be identified.After adding coupling signals to the cable, no significant effective signals can be detected using flexible coils and receiving boxes. It is recommended to stay about 3 meter
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What are the steps required for oil chromatography analysis?
2025-04-09The oil chromatography analyzer under UHV power can help many power workers conduct various power tests more conveniently.Chromatography analyzer, also known as gas chromatography analyzer. According to the analysis needs of actual samples, instant vaporization injection of packed columns, injection of large-diameter capillary columns, split flow injection of capillary columns, constant volume gas injection of flat rotary valves can be achieved for pyrolysis chromatography.During the use of transformers, it is important to ensure the safety of the machine as much as possible. If problems during the use of transformers need to be discovered in a timely manner, it involves chromatographic analysis of transformer oil. How to conduct chromatographic analysis?It mainly consists of the following steps:1. Take out a certain amount of transformer oilFirstly, prepare a certain amount of transformer oil. After the color of the transformer oil changes, use a test tube or syringe to extract a cert
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The main uses and identification methods of grounding resistors
2025-04-09The grounding resistance tester under UHV power can help many power workers conduct various power tests more conveniently.The grounding resistance tester is a resistance measurement device mainly used for measuring grounding resistance, soil resistivity, grounding voltage, AC current, and leakage current in power, telecommunications, meteorological oil fields, construction, lightning protection, industrial electrical, and other fields. Equipment. But different models or environments use different resistance testers.There are several types of grounding resistance measuring instruments, including clamp type (double clamp type), large grounding grid grounding, digital, etc. They not only differ in product characteristics, but also in measurement methods. People usually think that as long as resistance can be measured, but in fact, if mismatched measuring instruments are chosen, not only will it be impossible to accurately measure resistance, but it will also waste unnecessary time and lab
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Four common problems with insulation resistance tester
2025-04-08The insulation resistance tester under UHV power can help many power workers conduct various power tests more conveniently.The insulation resistance tester uses the tested voltage to excite the device or network, and measures resistance using Ohm's law. A large change in insulation resistance indicates potential faults. Therefore, when conducting tests, we need to regularly calibrate the megohmmeter to ensure that the instrument itself has not changed over time.The insulation resistance tester can be used to measure the resistance of various insulation materials, transformers, motors, cables, electrical equipment, etc. Next, let's take a look at some common problems with it.1. What does the output short-circuit current representTransformers with long cables, motors, and multiple windings belong to capacitive loads. When measuring the resistance of such objects, the output short-circuit current can reflect the internal resistance of the output high-voltage source in the megohmme
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Where is the insulation resistance tester suitable for
2025-04-08The insulation resistance tester under UHV power can help many power workers conduct various power tests more conveniently.In daily life and work, the insulation resistance of all electrical devices and equipment must comply with the requirements of relevant specifications and standards to ensure the safety of on-site operations. Whether it is cables, segmented protection equipment, motors, generators, etc., their conductor parts must be isolated with high insulation resistance materials to prevent current from flowing out.Over time, the insulation quality may decrease due to the environment, operating conditions, or other external forces in which the equipment is located. It reduces the resistivity of insulation materials, thereby increasing leakage current, which may cause serious accidents, endanger personal life and property safety, and may lead to factory shutdown and economic losses.The insulation resistance tester is used to measure the resistance of various insulation materials
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Test Method for Capacity Characteristics of Transformers for Capacity Calculation
2025-04-07The UHV power professional production transformer capacity tester can help many power workers conduct various power tests more conveniently.There are many methods for testing and calculating the capacity of transformer capacity testers. Today, let me briefly introduce the testing and calculation method for transformer capacity.Capacity is calculated based on the load rate β M at the highest efficiency of the transformerWhen the calculated load of the building is determined, the total installed capacity of the distribution transformer is:S=Pjs/βb×cosφ2 (KVA) (1)In the formula, Pjs - calculated active load of the building in KW;Cos φ 2- compensated average power factor, not less than 0.9;β B - Load rate of transformer.Therefore, the determination of transformer capacity depends on the selected transformer load factor β B.We know that when the transformer load rate is:The highest efficiency is achieved when β B=β M=Po/PKH (2)In the formula, Po represents the no-load loss of the transforme
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What are the characteristics of cable fault tester?
2025-04-03The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.With the advancement of social technology, the application of technology is very extensive in various aspects of daily life, from travel to water, gas, electricity and other fields, which are very safe and convenient. However, many people have concerns about the installation of raw materials, material selection or overhead of circuit lines in communication or electrification channels. I don't know much about it. In fact, during the entire process, if there is a problem with the cable, it is difficult to determine the problem and repair situation. Therefore, cable fault testers play a very important role in this regard. What are the specific characteristics of cable fault testers?The cable fault tester is mainly used to measure cable fault detection. The cable fault tester has complete functions and is very accurate. It is safe to use quickly. The cable fault tester mainl
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Selection and use of microampere meter in DC withstand voltage test
2025-04-02The DC high-voltage generator under the UHV power company can help many power workers conduct various power tests more conveniently.DC high voltage generator is used to detect the insulation strength of DC precision power supply and converter station equipment and insulation materials under high DC voltage, the corona and ion current of DC power lines and their effects, as well as the leakage current testing equipment of AC and DC power supplies. In addition, it can also serve as a power source for other high-voltage testing equipment, such as impulse voltage generators, impulse current generators, oscillation circuits, etc. Micro ammeter is an important component of DC high voltage generator, used to detect leakage current in voltage testing.When using a microampere meter for a DC high-voltage generator, the following precautions should be taken. The wiring of the microampere meter for a DC high-voltage generator is unreliable or not properly handled during testing, which can easily c
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Reasons for inaccurate test results of grounding resistance tester
2025-04-02The grounding resistance tester under UHV power can help many power workers conduct various power tests more conveniently.The digital grounding resistance tester abandons the traditional manual power generation mode. The grounding resistance tester adopts advanced medium to large integrated circuits. The digital grounding resistance tester adopts DC/AC conversion technology, combining the three terminal button and four terminal button measurement methods into a new type of grounding resistance meter. There are many factors that can cause inaccurate readings of grounding resistance in lightning protection testing of grounding resistance testers.1. Due to the fact that the grounding resistance tester tests the grounding resistance of the grounding body through the transmission and reception current of the iron drill rod, there may be mutual interference and errors when the distance between two iron drill rods and between two drill rods and the grounding body is too close. Therefore, in t
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