Wuhan GDZX Power Equipment Co., Ltd Company News

The accuracy of cable fault location is highly influenced by environmental conditions and various technical factors. Understanding these influences can guide the selection of suitable cable fault locators. Below are the key factors affecting fault location accuracy and essential technical criteria to consider when choosing a cable fault locator. Factors Affecting Cable Fault Location Accuracy Noise Interference Environmental Noise: High traffic areas, construction sites, or crowded spaces can introduce significant noise interference, which disrupts accurate readings. Background noises like engines, horns, and machinery can affect the locator's stability. To counteract this, use a locator with static noise reduction features to filter out environmental noise and enhance accuracy. Continuous Noise Sources Constant Machinery Noise: Continuous noise from nearby motors, fans, or pumps can cause the digital display to become unreliable. In such cases, using a locator with synchronous sound and electrical detection helps distinguish fault signals from background noise. Temperature Variation Temperature Sensitivity: The locator’s accuracy may be affected by extreme temperature variations, as the refractive index of the transmission medium (air or polymer materials) changes with temperature. This can cause deviations in readings, especially in very high or low-temperature environments. Humidity and Altitude Humidity: High humidity may dampen internal components, impacting the device’s performance. Moisture-proof measures are essential in humid environments to maintain accuracy. Altitude: High altitudes can affect pressure and temperature conditions, influencing measurement accuracy. Many cable fault locators are rated for operation below certain altitudes (e.g., 4500m) to ensure reliable results. Cable Characteristics Cable Length: Longer cables experience greater signal attenuation, which weakens the reflected signal and reduces measurement accuracy. Signal strength must be considered when locating faults in long cables. Cable Material: Different cable materials have different refractive indices. If the locator's refractive index setting does not match the actual cable material, errors may occur. Ensure compatibility with specific cable types for accurate readings. Other Factors Electromagnetic Interference: Strong electromagnetic fields can disrupt signal processing and transmission, leading to inaccuracies. Shielding the device may be necessary in high-interference environments. Ground Conditions: For underground cables, complex ground conditions (such as high soil moisture or rocky terrain) can increase positioning difficulty. In these situations, supplementary methods like ground-penetrating radar may be needed. Key Technical Criteria for Selecting a Cable Fault Locator When selecting a cable fault locator, it is essential to evaluate the following technical parameters to ensure accurate and reliable fault detection: Sensitivity and Noise Reduction Capability Choose a locator with high sensitivity to detect weak signals and noise reduction features, such as static noise filtering, for effective operation in noisy environments. Temperature Range and Stability Ensure the device can operate within the temperature range of your working environment. Locators with stable readings across varying temperatures will yield more consistent results. Moisture and Altitude Resistance For use in high humidity or elevated locations, select a locator with moisture-resistant features and verify its operational altitude rating for accurate performance in such conditions. Signal Attenuation Compensation Select equipment with features to compensate for signal attenuation, especially if you frequently work with long cables. Devices with adjustable gain or amplification settings are beneficial for maintaining signal integrity over long distances. Material Compatibility Ensure the locator’s refractive index settings are adjustable to match different cable materials, as compatibility with specific cable types is crucial for accurate measurement. Electromagnetic Shielding Devices with built-in electromagnetic shielding or those designed for high-interference environments are ideal for maintaining accuracy in areas with significant electromagnetic fields. Data Logging and Display Options Advanced locators with data logging capabilities help document test results, while clear, user-friendly displays improve accuracy and usability for less experienced operators. Portability and Durability Portability is important for fieldwork, while durability ensures long-term reliability. Look for lightweight, rugged designs with protective features if the equipment will be frequently transported. By considering these factors and selecting equipment with the appropriate specifications, you can ensure effective and accurate fault location in various environmental conditions, supporting efficient maintenance and troubleshooting.

Gas chromatography analysis of transformer oil is a critical diagnostic method in the power industry. This process helps monitor the health of transformers by detecting gas levels within the insulating oil, providing early warning signs of potential faults. Below is an explanation of its purpose, application, and key technical parameters to consider when selecting a transformer oil gas chromatography analyzer. What is Transformer Oil Gas Chromatography Analysis? Transformer oil gas chromatography analysis is a method for detecting dissolved gases in transformer insulating oil. As transformers operate, small amounts of gas can be generated due to insulation aging, electrical faults, or other internal issues. The types and concentrations of these gases reveal valuable information about the transformer's condition. For instance, gases like hydrogen, methane, ethylene, and carbon monoxide are often analyzed, as their presence or high levels can indicate overheating, arcing, or insulation breakdown. Purpose of Transformer Oil Gas Chromatography Analysis Early Fault Detection: By identifying unusual gas concentrations, gas chromatography provides early warnings of transformer faults, enabling preventive maintenance and avoiding costly repairs or unplanned outages. Condition Monitoring: Regular oil analysis helps assess the overall condition of the transformer, indicating whether internal components are deteriorating over time. Fault Diagnosis: The types of gases detected help diagnose specific types of faults, such as electrical arcing, thermal overheating, or partial discharge, assisting maintenance teams in taking targeted action. Extend Transformer Life: By continuously monitoring and addressing issues before they escalate, gas chromatography analysis contributes to extending the transformer’s service life and optimizing maintenance schedules. Key Criteria for Selecting a Transformer Oil Gas Chromatography Analyzer When selecting a gas chromatography analyzer for transformer oil, consider the following technical parameters to ensure accuracy, reliability, and usability: Detection Range and Sensitivity The analyzer should have a wide detection range and high sensitivity to detect even low concentrations of key gases like hydrogen, methane, and ethylene. High sensitivity is essential for accurate early fault detection. Multi-Gas Detection Capability Choose an analyzer that can detect multiple gases simultaneously, as analyzing various gases is critical for accurate fault diagnosis. The ability to detect standard gases such as hydrogen, methane, acetylene, ethylene, and carbon monoxide is essential. Measurement Accuracy and Stability High accuracy and stable performance are crucial for precise readings over time. Instruments with low detection limits and high repeatability provide reliable results for condition monitoring. Automatic Calibration and Data Logging Automatic calibration simplifies usage, ensuring accurate results with minimal manual intervention. Data logging capabilities are also beneficial for tracking gas levels over time and detecting trends that indicate developing faults. Analysis Speed Faster analysis allows for quicker diagnostics and real-time condition monitoring. For critical applications, select an analyzer that delivers results within a short time frame to support rapid decision-making. User-Friendly Interface A clear, user-friendly interface is essential, especially for less experienced operators. An intuitive display with easy-to-navigate menus simplifies operation and reduces training requirements. Portability and Durability If the analyzer will be used for on-site testing, portability is important. Look for a lightweight, durable model designed to withstand harsh field conditions if frequent transportation is required. Safety and Compliance Standards Ensure the analyzer complies with relevant safety and industry standards, such as IEC or ASTM, for reliable performance and safe operation in power industry environments. By choosing a gas chromatography analyzer that meets these technical requirements, you can ensure effective monitoring, fault detection, and maintenance planning for transformers, ultimately contributing to the reliable operation and extended lifespan of power equipment.

Working Principle of VLF Hipot Tester: The VLF (Very Low Frequency) Hipot Tester is designed to perform dielectric strength testing on high-voltage electrical equipment such as cables, transformers, and insulators. Unlike traditional AC hipot testers that operate at power frequency (50/60 Hz), the VLF tester uses a low-frequency voltage, typically in the range of 0.1 Hz to 0.1 kHz, to apply a high voltage to the equipment under test (EUT). The VLF Hipot Tester generates a very low frequency alternating voltage, which is applied to the insulation of the equipment for testing. This lower frequency is beneficial as it minimizes the capacitive charging current, which is especially useful for testing long cables or large equipment with high capacitance. The tester typically works by using a high-voltage transformer or an inverter that steps up the low input voltage to the required testing voltage.   Common Faults of VLF Hipot Tester: Insufficient Output Voltage Cause: Insufficient output voltage can occur due to a malfunctioning high-voltage transformer, issues with the internal capacitors, or a malfunction in the control circuit. Solution: Check the output voltage settings and inspect the transformer and control circuits for any defects or damages. Verify the calibration of the tester. High Leakage Current Cause: A high leakage current reading during testing typically suggests a fault in the insulation of the test object (e.g., a breakdown or deterioration of the cable or equipment insulation). Solution: If the tester shows excessive leakage current, the equipment being tested is likely defective. The tester's leakage current meter should be checked for calibration issues. Overvoltage Trip or Fault Cause: The VLF tester may trip or stop working if an overvoltage condition is detected. This could be caused by a fault in the EUT, a failure in the tester's voltage regulation system, or a misconfiguration of the voltage settings. Solution: Verify the test voltage settings and ensure that they are appropriate for the equipment under test. Check the EUT for faults, and inspect the tester for any overvoltage protection issues. No Output Voltage Cause: This can occur due to failure in the primary circuit components, including power supply issues, broken fuses, or faulty internal connections. Solution: Check the power supply connections, replace any blown fuses, and inspect the internal wiring and connections for continuity. Inaccurate Test Results Cause: Inaccurate readings during testing may be caused by defective components, such as the voltage measurement circuitry or the reference electrodes. Solution: Perform a calibration of the tester, checking the measurement system and verifying the operation of voltage sensors and reference connections. Erratic Display or No Display Cause: An erratic display or no display at all can result from malfunctioning control boards, loose connections, or faulty display screens. Solution: Inspect the control board and display wiring for any faults. If the display remains unresponsive, consider replacing the control unit or screen. Overheating Cause: Overheating of the VLF Hipot Tester can result from prolonged use without proper cooling, poor ventilation, or faulty cooling systems. Solution: Ensure the tester is being used within the specified operating limits and that adequate ventilation is in place. Check the cooling fans or heat sinks for proper function. Noise or Interference Cause: High-frequency noise or electrical interference can occur due to poor grounding or electromagnetic interference (EMI) in the testing environment. Solution: Check the grounding of both the VLF tester and the equipment under test. Additionally, ensure that the testing environment is free from sources of electromagnetic interference. Failure to Complete the Test Cycle Cause: The tester may fail to complete a test cycle due to software or hardware issues, such as a malfunctioning microcontroller or sensor, or issues with the timing circuits. Solution: Perform diagnostic tests to identify and troubleshoot the source of the failure. Update or reset the software, and check for hardware failures.   Common Fault Cause Solution Insufficient Output Voltage Malfunctioning high-voltage transformer, issues with internal capacitors, or control circuit failure. Check output voltage settings, inspect transformer and control circuits for defects, calibrate tester. High Leakage Current Fault in the insulation of the test object, breakdown or deterioration. Inspect equipment under test for insulation failure, verify leakage current meter calibration. Overvoltage Trip or Fault Overvoltage condition in EUT or misconfiguration of voltage settings. Verify test voltage settings, inspect EUT for faults, check overvoltage protection system. No Output Voltage Power supply issues, broken fuses, or faulty internal connections. Check power supply connections, replace blown fuses, inspect internal wiring for continuity. Inaccurate Test Results Defective components, voltage measurement circuitry, or reference electrodes. Calibrate tester, check voltage sensors, verify proper reference connections. Erratic Display or No Display Malfunctioning control board, loose connections, or faulty display screen. Inspect control board and wiring, replace unresponsive display or control unit if needed. Overheating Prolonged use without cooling, poor ventilation, or faulty cooling system. Ensure adequate ventilation, check fans or heat sinks for proper function, avoid overuse. Noise or Interference Poor grounding or electromagnetic interference in the testing environment. Check grounding of tester and equipment, ensure the environment is free from EMI. Failure to Complete Test Cycle Software or hardware issues, malfunctioning microcontroller or sensor, or timing circuit problems. Perform diagnostic tests, reset or update software, check for hardware failures. Key Considerations for VLF Hipot Tester Maintenance: Routine Calibration: Regular calibration of the tester is essential to ensure accurate test results. This helps detect any potential malfunctions early on. Proper Storage: Store the VLF tester in a dry, cool environment to avoid potential damage due to excessive humidity or temperature fluctuations. Testing Environment: Always perform testing in an environment with stable voltage and minimal electromagnetic interference to avoid false results. Safety: VLF Hipot testers generate very high voltages and should be used with care. Always follow the manufacturer’s instructions for operation, safety, and maintenance. Ensure that all personnel are properly trained and equipped with the necessary personal protective equipment (PPE). By maintaining the VLF Hipot Tester and addressing common faults promptly, operators can ensure reliable and safe high-voltage testing, maintaining the integrity and reliability of electrical equipment.

The portable oil particle counter operates based on the optical obstruction (shading) method, which is defined by international standards such as the International Hydraulic Standards Committee (ISO). The core working principle involves laser light scattering. Here's a detailed breakdown of the process: Laser Scanning: The oil sample is introduced into the counter, where it is illuminated by a laser beam. Particle Interaction: As the laser light passes through the oil sample, it interacts with any particles present. The particles cause the laser light to scatter. Light Scattering: The scattered light intensity is directly proportional to the size of the particle. Larger particles scatter light with greater intensity, while smaller particles scatter light less intensively. Data Analysis: By analyzing the intensity and pattern of the scattered light, the counter calculates the number, size distribution, and concentration of particles in the oil sample. In this way, the portable oil particle counter can accurately determine both the size and quantity of particles present in the oil, providing a comprehensive understanding of the oil’s contamination level. Application Scenario Analysis The portable oil particle counter is an essential tool in various industries for maintaining the health and longevity of machinery and systems that depend on oil as a lubricant or coolant. Here’s an overview of its application across different fields: 1. Industrial Machinery Maintenance Application: In industries such as manufacturing, power generation, and mining, machinery often operates in environments with high stress and pressure. The oils used for lubrication or cooling can become contaminated with particles like metal debris, dirt, or dust. Purpose: Regular use of the portable oil particle counter can ensure that oil contamination levels are within acceptable limits, preventing premature wear and damage to machinery components. Benefits: Early detection of oil contamination can help prevent major mechanical failures, reduce downtime, and extend the lifespan of equipment. It also helps in scheduling timely oil changes or filtering processes to avoid costly repairs. 2. Aerospace Industry Application: In the aerospace sector, hydraulic fluids, lubricating oils, and other fluids are critical to the safe operation of aircraft and spacecraft. Contaminated oil can impair system efficiency and lead to equipment malfunctions. Purpose: The portable oil particle counter is used to monitor and maintain the purity of oils used in aviation equipment such as engines, landing gear systems, and hydraulic systems. Benefits: This helps ensure the safety and reliability of aircraft, as well as reducing the risk of accidents due to oil contamination. The ability to monitor oil quality on-site also speeds up maintenance processes, enhancing operational efficiency. 3. Automotive Maintenance Application: Portable fluid particle counters are widely used in automotive maintenance, particularly for engine oil analysis. Particles such as wear debris from engine components or contaminants introduced during operation can affect engine performance. Purpose: By detecting and quantifying particles in engine oils, the tool can identify abnormal wear patterns or degradation in oil quality, signaling potential engine issues. Benefits: It allows for proactive maintenance or oil replacement, preventing engine failure, extending vehicle life, and improving fuel efficiency. 4. Oil and Gas Industry Application: In the oil and gas industry, hydraulic oils, turbine oils, and transformer oils are commonly used in drilling rigs, pumping stations, and offshore platforms. The contamination of these oils can affect the performance of vital equipment. Purpose: Portable oil particle counters help monitor the contamination levels of fluids used in critical equipment to ensure optimal performance. Benefits: Maintaining oil quality helps avoid downtime, reduces the risk of equipment failure, and ensures continuous operation in harsh environments. It also reduces operational costs by extending oil service life. 5. Power Generation Application: In power plants, large turbines and transformers rely on clean oils for cooling and lubrication. Contaminated oils can lead to overheating, inefficiency, and potential breakdowns. Purpose: The particle counter is used to monitor the condition of oils in transformers, turbines, and other vital equipment. Benefits: Ensures the operational efficiency of power generation systems, reducing the likelihood of failures and maintaining system reliability. 6. Laboratories and On-site Testing Application: Laboratories often use portable oil particle counters for oil contamination testing. This also applies to on-site testing for quality assurance during the manufacturing process of oils and lubricants. Purpose: To quickly and accurately assess the contamination levels in oils during production or after a service operation. Benefits: Provides reliable and immediate results, aiding in timely corrective actions and helping maintain the consistency and quality of oils used in industrial operations. Technical Specifications The portable oil particle counter is capable of measuring particles in various types of oil and fluids, including: Hydraulic oils Lubricating oils Transformer oils (insulation oils) Turbine oils Gear oils Engine oils Aviation kerosene Water-based hydraulic oils Phosphate esters Shale oil It is widely applicable in industries such as aerospace, power generation, petroleum, chemical processing, automotive manufacturing, and metallurgy. Conclusion The portable oil particle counter is an indispensable tool for industries where oil contamination directly impacts machinery performance and reliability. It is an efficient, quick, and portable solution for on-site testing, enabling proactive maintenance and reducing the risk of costly repairs. Through its precise particle size and count analysis, it plays a vital role in ensuring that fluids are within the required standards for optimal operation across various sectors.

Partial discharge (PD) testing is critical in assessing the condition of electrical equipment, such as transformers, high-voltage cables, and switchgears. It helps identify insulation weaknesses, which can potentially lead to catastrophic failures. The partial discharge detection process relies on several principles, technologies, and sensors. Below, we will detail the basic principles of PD detection, the key selection parameters for PD testing equipment, and the standards that guide the testing process.   Method Principle Frequency Range Advantages Challenges/Interference Transient Ground Voltage Electromagnetic waves accumulate in the grounded metal parts near the discharge point, generating transient ground voltage signals. 3-100 MHz Ideal for monitoring large numbers of devices in a power grid. Interference from other equipment like lighting systems, semiconductor switch components, and discharge tubes. Ultrasonic Wave PD generates sound waves with a wide frequency spectrum. Below 20 kHz can be heard by human ear, while above 20 kHz requires ultrasonic sensors. Tens of Hz to several MHz Highly sensitive, detects PD even in challenging environments where other signals may be hard to detect. Requires ultrasonic sensors for signals above 20 kHz. Ultra-High Frequency (UHF) Detects high-frequency electromagnetic waves generated during partial discharge events in power equipment. 300 MHz - 1.5 GHz Highly sensitive, avoids corona interference, and is effective in live detection, defect identification. Possible interference from nearby equipment producing signals below 300 MHz. High-Frequency Current Detects pulse currents generated by partial discharge, which propagate through the grounding system of the equipment. High-frequency pulse currents Non-invasive method; equipment does not need to be shut down, making it simple and reliable. Requires high-frequency current sensors (HFCT) and may need careful signal processing. Key Selection Parameters for PD Testing Equipment Parameter Description Frequency Range The frequency range must match the specific detection method (e.g., 3-100 MHz for transient ground voltage, 300 MHz-1.5 GHz for UHF). Sensitivity High sensitivity is necessary for detecting low-level partial discharge events and ensuring early detection. Signal Processing Advanced processing is needed to differentiate PD signals from interference. Real-Time Monitoring Ability to provide real-time monitoring and diagnostics of partial discharge events for proactive maintenance. Non-Invasive Testing Non-invasive methods like HFCT sensors allow for PD monitoring without shutting down the equipment, reducing downtime. System Compatibility The equipment should be compatible with various electrical systems such as transformers, cables, and switchgear. Partial Discharge Testing Standards Standard Description IEC 60270 Specifies test methods for partial discharge measurements in high-voltage equipment. IEC 60480 Guidelines for partial discharge testing in SF6-insulated electrical equipment. IEEE 1434 Guide for partial discharge testing of shielded power cable systems. This table provides a comprehensive view of the basic principles, advantages, challenges, key selection parameters, and relevant standards for partial discharge detection methods.

The transformer comprehensive testing bench is a sophisticated testing system designed for evaluating various parameters of transformers. It integrates multiple functions to perform comprehensive tests, including transformer ratio testing, DC resistance testing, insulation resistance testing, pulse testing, and more. This system allows for the consolidation of all these testing capabilities into a single platform for efficient and accurate transformer diagnostics. Key Components of the Transformer Comprehensive Testing Bench The transformer comprehensive testing system is composed of the following four main components: Transformer Comprehensive Test Bench: This is the primary platform where the transformer is placed for testing. It supports a range of electrical and mechanical testing functions necessary to evaluate transformer performance. The test bench is designed for secure transformer positioning during various tests. Low-Voltage Control Cabinets: These cabinets are responsible for controlling and regulating the low-voltage power supply used during transformer testing. They ensure that the testing environment adheres to specific voltage standards and safety requirements. Intermediate Frequency Generator Sets: This component generates intermediate frequency signals that are used for specific tests such as pulse testing and dielectric testing. These generators allow for accurate simulations of different operating conditions and help assess the transformer's response to varying frequencies. Power Frequency Withstand Voltage Test Systems: This system is used to test the ability of transformers to withstand power-frequency voltages, simulating operational stress. It is crucial for assessing the insulation and overall durability of the transformer under different voltage conditions. Additional Functional Components In addition to the core components, the transformer comprehensive testing system also includes several important functional systems that work together to ensure accurate data collection and processing: Industrial Computer and Data Processing Software System: This system is responsible for controlling the overall testing process, collecting data, and performing the necessary analysis. It interfaces with the various testing modules and aggregates test results for evaluation. The software processes the collected data and provides detailed reports, allowing users to interpret results and make informed decisions. Data Collection System for Each Testing Unit: This system collects real-time data from each testing unit, such as the transformer ratio, insulation resistance, DC resistance, and other parameters. It acts as the main interface between the physical testing equipment and the data processing software, ensuring that all test results are accurately captured and recorded. Strong Current Control and Instrument Monitoring System: This system is responsible for managing the high-current testing required for some transformer tests, such as insulation resistance testing. It ensures that the current levels are controlled and within safe operating limits. It also monitors the performance of the testing instruments, ensuring reliability and accuracy during the testing process. Human-Machine Interface (HMI) Comprehensive System: The HMI provides the user interface for operators to interact with the system. It displays test results, provides instructions, and allows users to control and monitor the testing process. The HMI is designed to be intuitive, offering operators easy access to critical data and control functions. Working Principle of the Transformer Comprehensive Testing Bench The working principle of the transformer comprehensive testing system is based on an integrated approach where all components collaborate to perform a full range of tests on transformers. Here’s how the system works: Transformer Setup: The transformer is placed on the transformer comprehensive test bench, which secures the transformer in position during the tests. Voltage Application: The low-voltage control cabinets regulate the input power and control the voltage levels required for each type of test. The system ensures that the transformer is exposed to different voltage levels as needed for ratio, insulation, and withstand voltage tests. Signal Generation: The intermediate frequency generator sets create the necessary test signals, especially for complex testing like pulse or dielectric tests. These signals simulate various operating conditions to assess how the transformer performs under different frequencies and stress scenarios. Data Acquisition: The data collection system continuously collects measurements from various testing units during the process. It gathers critical parameters such as voltage, current, resistance, and insulation quality. Data Processing and Analysis: The data collected by the system is processed by the industrial computer and data processing software. This software analyzes the results and generates reports that provide an in-depth look at the transformer's performance, including any issues or areas requiring attention. Control and Monitoring: The strong current control and instrument monitoring system ensures that the testing process proceeds without exceeding safe operational limits. It maintains precise control over high current testing scenarios to prevent equipment damage and ensure reliable results. User Interface: Operators use the HMI system to monitor the test progress, view real-time data, and control the test procedures. The HMI allows for seamless communication between the operator and the system, facilitating efficient operation. Core Technical Parameters The transformer comprehensive testing system is equipped with a wide range of technical parameters, including: Test Voltage Range: Adjustable voltage levels for testing various transformer types, from low-voltage to high-voltage transformers. Current Capacity: The system supports both low and high current tests, ensuring versatility in transformer testing. Insulation Resistance Measurement: High-accuracy insulation resistance testing to evaluate the integrity of transformer insulation. Frequency Range: The system supports a broad range of frequencies for different testing scenarios, including standard power frequency and intermediate frequencies. Measurement Accuracy: High precision in measuring parameters like ratio, resistance, and insulation resistance to ensure test reliability. Pulse Testing: Ability to generate and measure pulse signals for testing transformer dielectric strength and response to transient conditions. Safety Features: Built-in safety mechanisms to handle high-current and high-voltage tests, ensuring the protection of both the equipment and operators. Conclusion The transformer comprehensive testing bench is an advanced and versatile system that allows for thorough testing and evaluation of transformer performance. Its modular components, including the test bench, control cabinets, generator sets, and power frequency systems, work together to ensure a seamless and comprehensive testing process. By offering customized functionalities, it can meet specific user needs and provide highly accurate data for transformer maintenance, quality assurance, and performance evaluation.

The DC circuit breaker ampere-second testing system is designed to evaluate the performance of DC circuit breakers, particularly in terms of their current-limiting capabilities, tripping characteristics, and overall health within DC power distribution systems. This system tests several key attributes related to the breaker’s operation, ensuring that it can effectively protect circuits by responding appropriately to fault conditions. Principle of Testing The principle behind the DC circuit breaker ampere-second testing system revolves around simulating fault conditions in a controlled environment to determine how the breaker responds. The "ampere-second" value is the product of the current and the time it takes for the circuit breaker to trip under fault conditions. The system measures this time and current threshold to ensure that the breaker can limit the fault current within a safe range, thus preventing damage to the electrical system and maintaining the integrity of the circuit. The ampere-second test specifically checks how much energy (in terms of current over time) the circuit breaker can withstand and clear. This is critical for ensuring that the breaker can protect the system from high fault currents and prevent unnecessary trips or damage to equipment. Test Process Preparation: Connect the Testing Equipment: The DC circuit breaker is connected to the testing system, which includes current injection sources, sensors, and monitoring equipment. Set Test Parameters: Parameters such as test current, test time duration, and the specific type of test (e.g., trip time, current on/off) are set according to the breaker’s specifications. Testing the Ampere-Second Characteristics: The system injects a pre-determined current into the DC circuit breaker and monitors the breaker’s ability to trip within a specified time. The system measures how long the breaker takes to interrupt the current and what the corresponding current levels are when the breaker opens. Current On/Off Test: This test checks the breaker’s ability to handle both the making and breaking of the current. The system will evaluate how well the breaker performs during the closing (making) and opening (breaking) of the circuit under various load conditions. Trip Test: This test evaluates the time it takes for the breaker to trip when a fault current is injected, and the conditions under which it trips. This simulates real-world short-circuit or overload conditions to ensure the breaker responds correctly. Differential Coordination Test: The differential coordination test checks the coordination between multiple breakers in a system. This ensures that the breaker closest to the fault trips first, while others remain unaffected, thus preventing unnecessary disconnection of power. Internal Resistance Test: This test measures the internal resistance of the DC circuit breaker, ensuring that it has minimal resistance during operation, which could affect its performance and safety. Full-Point and Spot Testing: Full-point testing involves checking multiple operational parameters under various conditions, ensuring that the breaker operates correctly across a range of fault scenarios. Spot testing may focus on specific aspects like trip time or current handling, providing a snapshot of the breaker’s performance. Purpose of the Testing The primary purpose of the DC circuit breaker ampere-second testing system is to ensure the breaker’s ability to protect the electrical network by interrupting fault currents in a timely manner. This helps: Prevent Overstepping Trips: Ensuring that the breaker trips only under fault conditions and not due to normal operating surges. Avoid Large-Scale Power Outages: Ensuring that only the circuit with the fault is interrupted, leaving the rest of the system in operation. Increase Reliability: By testing and confirming the performance of DC circuit breakers, the reliability of the DC power distribution network is enhanced, ensuring continuous and safe operation. Improve System Stability: Prevents cascading failures by ensuring that the circuit breakers respond correctly to faults and protect downstream equipment. Key Selection Parameters Affecting Testing Several technical parameters influence the selection of equipment for the ampere-second testing system and the effectiveness of the tests: Parameter Description Rated Current (1A–500A) The system must be able to test DC circuit breakers within this current range to ensure accurate performance evaluation. Test Current Injection Range The system should be able to inject fault currents ranging from the lowest operational value to the maximum breaking capacity of the breaker. Trip Time Measurement Precision in measuring the trip time is critical for assessing the breaker’s performance during fault conditions. Test Duration The testing system should ensure that the breaker is subjected to fault conditions for an appropriate time to evaluate its interrupting capabilities. Break Time Measurement The system must measure the exact time the breaker takes to open and disconnect the circuit once it detects a fault current. Internal Resistance Measurement The system must be capable of measuring the internal resistance of the breaker to ensure it is low and does not affect its performance. Differential Coordination The ability to test the coordination between multiple breakers in a distribution system, ensuring proper sequencing during fault events. Full-Point vs. Spot Testing The ability to conduct comprehensive full-point testing versus focused spot tests on specific parameters like trip time, current handling, etc. Conclusion The DC circuit breaker ampere-second testing system is crucial for evaluating the performance of DC circuit breakers in power distribution networks. By testing various characteristics such as ampere-second values, trip times, and differential coordination, it ensures that the breaker can effectively protect the system from faults, preventing large-scale outages and improving the overall reliability and stability of the DC power distribution network.

To detect potential short circuit hazards in power transformers, various equipment and methods can be used to monitor their condition and prevent damage due to short circuits. The most common devices for early detection and monitoring include: 1. Transformer Winding Resistance Tester Principle: This device measures the resistance of the transformer windings to detect any potential faults, such as partial winding damage, loose connections, or improper insulation. An increase in resistance could indicate a short circuit or degradation of the transformer windings, which could lead to failures under short circuit conditions. 2. Partial Discharge Detector Principle: Partial discharge occurs when there are small electrical discharges in the insulation system of the transformer, typically due to defects or deterioration. By monitoring partial discharge, the device can detect early signs of insulation breakdown, which may eventually result in a short circuit. 3. Oil Gas Chromatograph or DGA (Dissolved Gas Analysis) Test Principle: The dissolved gases in transformer oil can indicate internal electrical faults or degradation, such as overheating, arcing, or short circuits. Analyzing these gases helps identify abnormal conditions that could eventually lead to a short circuit. 4. Transformer Monitoring System (Online Condition Monitoring) Principle: This system uses various sensors (temperature, pressure, current, voltage, etc.) to continuously monitor the condition of a transformer. It can detect anomalies in current or voltage that could signal the onset of a short circuit or an overload condition. It also checks for over-heating or abnormal temperature rises that can result from internal faults like short circuits. 5. Overcurrent Protection Relays Principle: These relays are designed to protect transformers from short circuits by sensing abnormal current levels and initiating a trip to disconnect the transformer from the circuit. When a short circuit occurs, the overcurrent relay detects the excessive current flow and sends a signal to the circuit breaker to open the connection, preventing damage. 6. Thermal Imaging Cameras Principle: Thermal imaging is used to detect hot spots in the transformer. If a transformer experiences abnormal heat, it could be a sign of a potential short circuit, winding failure, or overload condition. Regular monitoring with thermal cameras can identify overheating areas before they lead to severe damage. Conclusion: Using a combination of these testing and monitoring devices can help detect early warning signs of potential short circuit hazards in transformers. By identifying issues such as insulation breakdown, winding faults, or abnormal current, appropriate preventive measures can be taken to avoid severe damage and ensure the transformer operates safely within its design parameters.

Cable resonance withstand voltage test The resonant voltage withstand test method is to change the inductance and test frequency of the test system, so that the circuit is in a resonant state, so that most of the capacitive current on the test circuit and the inductive current on the reactor are offset, and the energy supplied by the power supply is only the study power consumed in the circuit, which is 1/Q of the capacity of the test product (Q is the resonant multiple of the system). Therefore, the capacity of the test power supply is reduced, and the weight is greatly reduced. The resonant withstand voltage test system can be divided into two kinds according to the regulation mode: the modulated induction type and the modulated frequency type. The adjustable inductance type resonant test system can meet the requirement of withstand voltage, but because of its large weight and poor mobility, it is mainly used in the laboratory. Frequency conversion series resonance voltage withstand test uses the inductance of the reactor and the capacitance of the subject to achieve capacitor resonance, and obtains high voltage and high current on the subject. It is a new method and trend of high voltage test at present, and has been widely used at home and abroad. Frequency conversion series resonance is a resonant current filter circuit, which can improve the waveform distortion of the power supply, obtain a better sinusoidal voltage waveform, and effectively prevent the harmonic peak to the test product. Frequency conversion series resonance works in the resonance state, when the insulation point of the subject is broken down, the current is immediately detuned, and the loop current rapidly drops to one tenth of the normal test current. When a flashover breakdown occurs, due to the loss of resonance conditions, in addition to the short circuit current immediately decreases, the high voltage also immediately disappears, and the arc can be extinguished. The re-establishment process of the recovery voltage is very long, and it is easy to disconnect the power supply when the flashover voltage is reached again, so it is suitable for the insulation withstand voltage test of high voltage and large capacity power equipment.   The frequency conversion resonance test system can not only meet the requirements of high voltage XLPE cable, but also has the advantages of light weight and good mobility, which is suitable for field test. After analysis and comparison, the frequency conversion series resonance test device uses a fixed reactor as a resonance reactor to achieve resonance in the way of frequency modulation, the frequency adjustment range is 30~300Hz, in line with the national standard "Electrical equipment handover test Standard" (GB50150-2006) recommended to use a frequency of 20~300Hz resonance voltage test. Notes on resonance withstand voltage test (1) Most of the resonant power supply products are high-voltage test equipment, which is required to be used by high-voltage test professionals, and should be carefully read the instruction manual before use, and repeated operation training. (2) The operator shall be no less than 2 persons. When used, the unit should strictly abide by the safety operation rules of high-pressure test. (3) In order to ensure the safety and correctness of the test, in addition to being familiar with the product manual, the test operation must be carried out in strict accordance with the relevant national standards and regulations. (4) Each connection line can not be connected wrong, especially the ground line can not be connected wrong, otherwise it can cause damage to the test device. (5) When the device is used, the output is high voltage or ultra-high voltage, must be reliably grounded, pay attention to the safe distance of operation. (6) Series resonance test system is the use of resonant reactor and the test product resonance to produce high voltage, that is to say, can produce high voltage is mainly to see whether the test product and resonant reactor resonance, so the test personnel in the analysis of the site can not produce the required high voltage, should analyze what damage the resonance conditions, the loop is connected and so on. (7) The series resonance test system of the excitation transformer has specific voltage and current requirements, in the selection of substitutes, must consider the voltage and current, can not use just the same capacity of the ordinary test transformer. GDZX is a professional manufacturer of secondary protection testing equipment, with a wide range of instruments and equipment to choose from. GDZX is at your service: 4000-828-027, for more information visit GDZX official website: www.gdzxdl.com。  

Cable insulation resistance test The test of cable insulation resistance refers to the measurement of insulation resistance between cable cores and between cable cores and skin. It can preliminarily determine the defects of cable insulation aging due to moisture, and can also determine whether there are any defects in the insulation of the cable during the withstand voltage test. The DC resistance of the cable conductor can be measured using the bridge method or the voltage drop method. When measuring the DC resistance of the conductor of a phase cable, other phase cables can be used as voltage and current leads at the other end. The simple and basic method is the megohmmeter method Measuring cable insulation resistance with a megohmmeter The measurement of insulation resistance includes direct measurement method, comparison method, charging method, and self discharge method;   The direct method is a commonly used measurement method, which applies a known stable DC voltage to the tested workpiece. Determine the insulation resistance by the steady-state current of the tested object. Test methods for insulation resistance testers The L terminal is connected to the cable core, using a connection wire with high insulation resistance and being careful not to place it on the ground or come into contact with other objects. The E terminal of the megohmmeter is connected to the cable sheath and ground. To eliminate the impact of surface leakage current, the G terminal should be connected to the shielding ring of the insulation at the end of the cable core. For the sake of comparison, the insulation resistance values measured at different temperatures are generally converted into values at a temperature of 20 ℃ and a length of 1Km. Precautions for measuring cable insulation resistance Before the test, the conductor core and cable metal sheath must be grounded to fully discharge, and an appropriate megohmmeter must be selected based on the rated voltage of the tested cable At the same time, wipe the surface of the cable terminal clean and perform surface shielding. When measuring, the megohmmeter should be placed in a stable and free from significant vibration place, and the megohmmeter should be checked for normal operation according to relevant requirements; After each insulation resistance measurement, the cable should be discharged. The longer the grounding cable line, the longer the grounding time, usually no less than 1 minute. Guodian Zhongxing is a professional manufacturer of secondary protection testing equipment, the production of instruments and equipment, a variety of models to choose from. Guodian Zhongxing is at your service: 4000-828-027, for more information, visit GDZX official website:www.gdzxdl.com.

One of the Major events [undertakes power protection projects for 35 stadiums and 107 hotels in the 7th World Military Games]     After winning the bid for the Baoding Power Project, we are facing severe tests and challenges. This is not only a political task, but also a basic guarantee for the smooth progress of the entire military games. Time is tight and tasks are heavy. In just three months, we successfully completed the power maintenance work of the opening ceremony of the Military Games with high standards of power protection specifications, effective organizational support, reliable technical measures, and strict work discipline. On October 18th, the 7th World Military Games, which attracted worldwide attention, opened in Wuhan. The wonderful opening ceremony attracted the attention of hundreds of millions of people around the world. Behind this wonderful, it is the silent adherence of all company personnel. Major event two [General industrial and commercial electricity sales services] 2019 is the second year of Hubei's power reform, and it is an important measure for the provincial government to continue to reduce the production and operation costs of operating enterprises. As of the end of this year, the accumulated electricity consumption reduction and exemption for industrial and commercial users through the sale of electricity purchase services has exceeded 11.4 million yuan. As more power users participate in the power reform, the barriers to entry will also decrease year by year, and more companies will enjoy the dividends brought by this wave of reform. Opportunities and challenges co-exist, hoping to be better next year! Major event Three [Electric Power Detection Equipment Exceeds 150 Million Output Value] In 2019, electric power testing instruments and power companies in various provinces across the country won the bid to complete the task and respond to the One Belt One Road strategy. Participated in the one-time operation of the 220KV power transmission and transformation project in the Congo, and achieved the power supply target to CNMC in advance.At the same time , The export international market grew steadily 10 million yuan sales , providing a strong guarantee for the construction of the national power grid! Major event Four [ Smart Energy Comprehensive Technology Services] In 2019, the provincial smart energy comprehensive technology platform developed by the State Grid NanRui Research Institute commissioned our company to conduct a trial run with several universities in Wuhan for trial. Grafting electricity measurement points, real-time information such as power loss and short circuit with data and graphs are displayed on the large LED screen, which greatly reduces the maintenance manpower and time, and achieves no-blackout treatment effect. Promote the use of most of the power consumption enterprises in the province in 2020 and beyond. At that time, enterprises will not need to hire professional electricians and maintenance personnel, which will reduce the burden for enterprises in disguise.     In 2020, we believe everything will be better!Thank new old customers for their support for GDZX in 2019. Our growth cannot be separated from your encouragement. GDZX will walk with you and focus on technical services and R & D to provide more Good product and technical support!  

      Recently, Wuhan GDZX Power Equipment Co., Ltd. ushered in a number of cooperation orders. The equipment cooperated with customers this time is the loop resistance tester independently developed and produced by GDZX.           The loop resistance tester produced by GDZX is designed by using a combination of high-frequency switching power supply technology and digital circuit technology. It is suitable for the measurement of the loop resistance of switch control equipment. The test current is 100A DC recommended by national standards. The loop resistance can be directly measured at a current of 100A and displayed digitally. The instrument has accurate measurement and stable performance, which meets the requirements of on-site high-voltage switch repair and high-voltage switch factory loop resistance test in the power and power supply departments.     After learning about our company's loop resistance tester products, the customer decisively placed an order for a total of 45 units. Currently, 22 units have been delivered and the remaining 23 units are in urgent production. GDZX adheres to the concept of "product quality is the most important, customer service is paramount", and provides high-quality products and services to customers and friends. We welcome friends from all walks of life to come and look forward to working with you for your sincere cooperation.