רשימת מוצרים
צור קשר
דוא"ל:qiao@hvtest.cc
נייד: +8615871365102
מה האפליקציה: +8615871365102
-
How to properly use and maintain a DC high-voltage generator?
2025-02-18The DC high-voltage generator under the UHV power company can help many power workers conduct various power tests more conveniently.DC high voltage generator, abbreviated as Zhigao. Strictly following the requirements to use a DC high-voltage generator and being familiar with the following precautions will make the operation safer and more convenient. In fact, DC high-voltage generators play a safety protection role in the field of power devices and are widely used. It is worth mentioning that there are many precautions to be taken when using and maintaining DC high-voltage generators. Below, Wuhan Defu Electric has listed some precautions to help you correctly use and maintain DC high-voltage generators.1、 Precautions for Maintenance of DC High Voltage Generator:1. Prevent foreign objects from entering the control box. If the control box has a fan, check if the fan is running properly. reach2. Check the dust prevention devices at all locations. If there is any damage or loose connecti
יותר -
In the series resonance experiment, automatic tuning of the device cannot be achieved,the reason for not being able to find the resonance point
2025-02-17The series resonance under UHV power can help many power workers conduct various power tests more conveniently.Phenomenon:The tuning curve is a straight line, and the instrument indicates no resonance point after tuningreason:Poor grounding of the circuit, incorrect wiring of the testing circuit, and open circuit of the instrument and equipmentElimination method:1) Check if the grounding device is reliable and if the grounding connection wire is disconnected;2) Check the on/off status of the high and low voltage coils of the excitation transformer; (Low voltage winding resistance; high voltage winding resistance at each output end vs high voltage tail)3) Check the continuity of each reactor; (Resistance of each winding)4) Check the continuity of the voltage divider signal line; (High and low voltage capacity)5) Check the continuity of the high and low voltage capacitor arms of the voltage divider; (Core 1 hole, shell 2 holes; 1 hole is disconnected from 2 holes)6) The device itself doe
יותר -
What are the operating skills of cable fault tester?
2025-02-14The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.The first point is that after connecting the circuit using the multi pulse method, if the test waveform is not ideal, it is normal to apply high voltage impact for the first time. Because the distance of the fault is not known in advance, the electrical strength of the fault point is unclear. If the impulse voltage is not high enough and the fault point is not penetrated by the impulse high voltage, the fault echo cannot be collected. You can only see the waveform of the open terminal. The pulse voltage must be increased until the fault echo is seen.Secondly, sometimes the fault point is far away from the testing end and the echo is weak. Therefore, it is necessary to adjust the "length selection" to obtain a stronger fault echo. The cable fault tester has three states: "short distance", "medium distance", and "long distance". Short range is suitable for fault detection with
יותר -
Precautions for testing the kinematic viscosity tester
2025-02-14The kinematic viscosity tester under the UHV power company can help many power workers conduct various power tests more conveniently.1. When using the instrument, the instrument casing must be well grounded;2. Before installing transformer oil in the constant temperature bath, do not turn on the heating control switch;3. The constant temperature medium in the bathtub shall not be lower than half of the upper part of the expansion part of the viscometer;4. Continuous use should pay attention to whether the oil level of the transformer in the constant temperature bath has decreased. If it is too low, it should be replenished at any time. If there are impurities in the transformer oil, they should be promptly treated, eliminated or replaced;5. Do not unplug or insert any connecting wires without unplugging the power plug;6. The constant of capillary viscometer should be safely backed up;7. Pay attention to replenishing cleaning solution and draining waste oil from the waste liquid storage
יותר -
Common problems and precautions of series resonance experimental device
2025-02-13The series resonance under UHV power can help many power workers conduct various power tests more conveniently.In the use of series resonance equipment, we often encounter some problems. For example, the problem of the fan not starting when using the series resonance equipment:1) Failure to press' fault reset 'after emergency stop, fault protection, and mismatch protection;2) Internal temperature too high, power component overheating protection;Troubleshooting method: Turn off the instrument power, let the instrument stand for about 30 minutes, turn on the power again, press the "Reset" button on the instrument panel, and then start the instrument.If the fan still cannot start, please contact the manufacturer. Please do not remove the instrument!In addition to the grounding wire of the power cord, the grounding pole of the product casing must also be grounded. To prevent electric shock, the grounding conductor must be grounded. Before connecting the input or output terminals of
יותר -
The usage method of transformer oleic acid value tester
2025-02-12The acid value tester under UHV power can help many power workers conduct various power tests more conveniently.In practical work, if electricians want to test the oleic acid value of transformers, they need to use an acid value tester. This equipment is a type of testing device used in transformer oil testing and is often needed. It is convenient and popular to use. So, how to use a specialized transformer oil acid value tester? This article will provide you with a brief introduction.The acid value tester adopts the principle of neutralization method. At room temperature, the microcomputer system internal control enterprise can automatically complete liquid addition, stirring, titration, and endpoint judgment. Adopting a touch sensitive LCD screen to develop time parameters for all resource management accounting work, the human-machine dialogue interface design is simple and friendly, the operation method is simple and convenient, and the research cycle for analyzing the average servi
יותר -
Precautions for DC withstand voltage test
2025-02-12The DC high-voltage generator under the UHV power company can help many power workers conduct various power tests more conveniently.1. Before testing, conduct a test on the cable and fully discharge it to the ground; Disconnect the devices connected at both ends of the cable and do not connect any other devices during the testing process; Clean the insulation surfaces at both ends of the cable head to reduce leakage current caused by the surface. If necessary, insulation barriers should be installed between the phases of the cable head.2. Safety measures such as fences should be taken at the testing site. Especially at the other end of the cable, a warning sign should be hung and a dedicated person should be assigned to guard to prevent outsiders from approaching, and to check whether the grounding wire and discharge rod are well connected.3. When applying pressure, the voltage should be gradually increased to prevent excessive charging current. After staying at 0.25, 0.5, 0.75, and 1.
יותר -
The steps for testing cable faults with a cable fault tester
2025-02-11The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.Step 1: First, use a rangefinder to measure the distance. In fact, the first step is to determine whether the cable fault is high resistance, low resistance, or grounding. Different testing methods have been adopted to address this situation. If it is a ground fault, use the low voltage pulse method of the rangefinder to directly measure the distance. If it is a high resistance fault, high-voltage pulse discharge method needs to be used to measure the distance, and auxiliary equipment such as high-voltage pulse capacitors, discharge balls, current limiting resistors, inductance coils, and signal samplers need to be used to measure the distance.Step 2: Find the path (if the path is clear, it can be omitted). When searching for a path, a signal (path signal generator) is added to the cable, which is then received by a receiver and used to determine the cable path along the pat
יותר -
Cleaning method for oil cup of insulation oil dielectric loss tester
2025-02-11The insulation oil dielectric loss tester under UHV power can help many power workers conduct various power tests more conveniently.Cleaning the oil cup is a very important preparation work when measuring the loss value of insulating oil with an insulation oil dielectric loss tester. Some unreliable measurement results are often caused by incomplete cleaning of the oil cup. Therefore, strict cleaning methods must be followed to obtain reproducible and reliable measurement results.When conducting the identification test of insulation oil loss coefficient, the oil cup should be thoroughly cleaned before each test. The cleaning steps are as follows:a. Completely remove the oil cup and clean all components with chemically pure petroleum ether (distillation range 60-90 ℃) and benzene in sequence.b. Rinse all components with acetone, then clean with neutral detergent.C. Boil all components in 5% trisodium phosphate in distilled water for 5 minutes, then rinse several times with distilled wat
יותר -
Cable aging and faults
2025-02-10The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.reason1. External force damage. Based on operational analysis in recent years, especially in Shanghai Pudong where the economy is rapidly developing, a considerable number of cable failures are caused by mechanical damage.2. Insulation is damp. This situation is also very common, usually occurring at cable joints buried directly or in ducts. For example, if the cable joint is not made properly or if the joint is made under humid weather conditions, it will cause water or steam to enter the joint. Over time, under the action of an electric field, water branches will form, gradually damaging the insulation strength of the cable and causing faults.3. Chemical corrosion. Directly burying cables in areas with acidic or alkaline effects often causes corrosion of the cable's armor, lead sheath, or outer protective layer. The protective layer may fail due to long-term chemical o
יותר -
What are the contents of insulation prevention test?
2025-02-08The insulation resistance tester under UHV power can help many power workers conduct various power tests more conveniently.Maintaining good insulation is crucial for high-voltage electrical testing equipment during operation. Therefore, every step of the equipment from production to use must undergo a series of insulation tests, including raw material testing during the production process, factory testing, handover testing, operation and maintenance insulation prevention testing, etc. Wait. Among them, handover testing and preventive testing of electrical equipment are two important types of testing. This section focuses on the content of insulation prevention tests.1. Insulation resistance testInsulation resistance testing is a widely used and convenient method in electrical equipment insulation testing. The magnitude of insulation resistance can effectively reflect the overall moisture, pollution, and severe overheating aging of the insulation. The commonly used instrument for testin
יותר -
How to solve the fault of the circuit resistance tester?
2025-02-08The circuit resistance tester under UHV power can help many power workers conduct various power tests more conveniently.1. [Phenomenon] When connected to a 220V AC power supply, the fan does not make any sound. When the "test switch" is pressed, the ammeter and micro ohmmeter do not display. 【 Reason 】 The 220V AC power supply is blocked, and the fuse is not installed or blown. 【 Exclusion Method 】 Check and exclude. The 100A instrument fuse will burn out again if it is not lower than 6A, and the factory will solve it. (Do not connect to DC or 380V AC power supply)2. 【 Phenomenon 】 Press the 'test switch', the ammeter displays no current, and the highest position of the micro ohmmeter displays' 1 '. [Reason] The 100A current circuit connection is incorrect. The tested switch is not closed. [Processing] Check the probe, reconnect it, and re clamp it. Turn off the switch.3. [Phenomenon] The test current is normal, but the highest micro ohm value is displayed as "1". [Reas
יותר -
The importance of dielectric strength testing of insulating oil
2025-02-07The specialized production of insulation oil dielectric strength tester for UHV power can help many power workers conduct various power tests more conveniently.As a medium filled in electrical equipment, insulating oil has many advantages such as insulation, heat dissipation, and arc extinguishing, and is widely used. For example, large power transformers use insulating oil for insulation and heat dissipation. But there is a discharge fault inside the transformer. Under the action of voltage, insulating oil undergoes a series of chemical reactions such as light, heat, and electricity. It is also crucial to regularly test the insulation oil during use in order to reduce its voltage resistance performance.The breakdown voltage of insulating oil is an indicator of its ability to withstand voltage inside electrical equipment and is one of the main means of inspecting the quality of oil insulation. Here we use an insulation oil dielectric strength tester produced by ultra-high voltage to co
יותר -
What is partial discharge (PD)?
2025-02-07The specialized production of partial discharge testers for UHV power can help many power workers conduct various power tests more conveniently.What is (partial discharge) PD and why do we need to test it?PD is a discharge that occurs in a localized area of insulation between two conductive electrodes, without completely bridging the gap (see IEC 60270) It may be caused by discontinuities or defects in the insulation system. PD activity is an indication of early medium voltage (MV) or high voltage (HV) insulation faults and is widely regarded as the best warning indicator for electrical insulation degradation of medium and high voltage electrical assets in power networks. Generally speaking, partial discharge occurs in systems with a voltage of 3 kV or higher; However, it should be noted that in some cases, PD may also occur at lower voltages (i.e. variable speed drive/variable frequency drive motors and LV designs). The typical driving factors for implementing PD plans include: suppor
יותר -
The use and maintenance of automatic motion viscosity tester
2025-02-06The kinematic viscosity tester under the UHV power company can help many power workers conduct various power tests more conveniently.Automatic kinematic viscosity tester refers to a kinematic viscosity tester suitable for measuring the kinematic viscosity of transparent and opaque liquids (including crude oil, light heavy oil, lubricant additives, etc.). The operating interface is simple, and the system has advantages such as self checking, self diagnosis, and fault prediction. For your better use, I will briefly introduce the relevant usage and maintenance methods.(1) Place the automatic motion viscosity tester on a stable workbench, connect the wires, install the sensor and thermometer, ensure that all switches are in the off position, connect the power cord, and pay attention to good grounding.(2) When placing the capillary tube, use a heavy hammer to adjust the three screws on the capillary tube holder to make the capillary tube in a vertical position.(3) Fill the bathtub with wate
יותר -
It is not recommended to use a thermal imager for partial discharge inspection
2025-01-22The specialized production of partial discharge testers for UHV power can help many power workers conduct various power tests more conveniently.It is not recommended to use a thermal imager for partial discharge inspectionThe thermal imager observes the infrared energy emitted by the target object. This electrical inspection means that we are searching for overheated electrical assets. For example, loose and corroded connections can generate higher resistance, resulting in higher temperatures, or unbalanced loads due to phase to phase temperature differences, or reduced liquid levels due to transformer oil leaks, which can be evident when using thermal imaging instruments correctly.However, partial discharge is a problem with thermal imagers. Thermal imaging depends on the current, and its power is proportional to the current multiplied by the square of the resistance (higher current leads to higher temperature, and higher resistance also leads to higher temperature). Partial discharge
יותר -
Common causes of cable faults
2025-01-22The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.Of course, cables are a fundamental component of wired networks. Their effectiveness has a significant impact on network connectivity and data transmission. Over time, manufacturers have improved the wires to make them more durable and resistant to interference. It is important to note that even the most skilled cables have their vulnerabilities. CableWholesale explores the common causes of cable failures so that you can make the wisest choices when selecting and installing wires for wired network settings.Insulation damageConductors are necessary for the transmission of electrical signals. When the quality of the conductor inside the cable is damaged, it is called insulation damage. Insulation damage is usually caused by the following reasons:1. Bending stress2. Wear and tear within the cable structure3. Wire breakageContinuity lossLike any other conductor, copper conductor
יותר -
Detecting partial discharge
2025-01-21The specialized production of partial discharge testers for UHV power can help many power workers conduct various power tests more conveniently.Detecting partial dischargeWe use two techniques to detect partial discharge, namely:Used for surface dischargeUltrasonic surface discharge detection using ultrasonic waves is a recognized worldwide method. Ultrasonic detection of discharge relies on detecting the sound emitted by the discharge. The emitted sound energy is a discharge centered on a frequency spectrum higher than the range of the human ear. Therefore, the instrument is used to move the frequency to a comfortable audible frequency, present it in the earphone, and measure the intensity on a simple scale.TEV detection for internal discharge was first developed 25 years ago. It has matured in the UK and is gaining increasing recognition worldwide. TEV detection relies on the voltage pulses generated on surrounding metal products when there is partial discharge inside the insulation.
יותר -
What is partial discharge?
2025-01-21The specialized production of partial discharge testers for UHV power can help many power workers conduct various power tests more conveniently.What is partial discharge?Partial discharge (PD) is a discharge or spark that bridges a small portion of insulation between two conductive electrodes. Partial discharge may occur at any point in an insulation system where the electric field strength exceeds the breakdown strength of the insulation material in that part. Partial discharge may occur on the surface of insulating materials (mainly due to pollutants or irregularities), inside bubbles in liquid insulation, in gaps in solid insulation, or around electrodes in gas (corona activity).Local emissionsThe energy emitted by partial discharge is as follows:Electromagnetic radiation, in the form of radio waves, light, and heatAcoustic emission, within the audible and ultrasonic rangeOzone and nitrous oxide gasThe evidence provided by partial discharge activity indicates that assets are deterio
יותר -
Global Karl Fischer Moisture Titimeter Market Report Segmentation
2025-01-20The trace moisture analyzer under UHV power can help many power workers conduct various power tests more conveniently.The Karl Fischer Moisture Titimeter Market Research Report closely monitors leading competitors through strategic analysis, micro and macro market trends and scenarios, pricing analysis, and an overall overview of market conditions during the forecast period. This is a professional and detailed report that focuses on primary and secondary drivers, market share, leading segments, and geographic analysis. In addition, the report also reviewed the main participants, major collaborations, mergers and acquisitions, as well as trend innovation and business policies.Main benefits for industry participants and stakeholders:1. The industry drivers, limiting factors, and opportunities covered by the research2. Hold a neutral view on market performance3. Recent industry trends and developments4. The competitive landscape and strategies of the main participants5. Covering potential
יותר
