Transformer Test Equipment

Dielectric damage measurement is a fundamental method in insulation testing, which can effectively detect both overall damp deterioration of electrical equipment insulation and localized defects. It is widely used in electrical manufacturing, electrical equipment installation, handover, and preventive testing. The dielectric damage measurement of transformers, reactors, capacitors, casings, and lightning arresters is the most basic method for assessing their insulation performance.

This method breaks through the traditional bridge measurement technique by using frequency conversion power supply technology, a microcontroller, and modern electronic technologies for automatic frequency conversion, analog/digital conversion, and data processing. It offers fast testing speed, high accuracy, automatic digital operation, and ease of use. The power supply utilizes a high-power switch, outputting 45Hz, 50Hz, and 55Hz pure sine waves with automatic voltage regulation, providing up to 500V. An automatic filter eliminates 50Hz interference, making it suitable for substation electromagnetic interference field tests.

It is widely used in the power industry for testing transformers, reactors, casings, capacitors, lightning arresters, and other equipment.

The device is a new generation of innovative CT and PT testing instruments, launched after extensive market research and certification by strict professional testing and certification authorities. The device adopts a high-performance processor and microcomputer control architecture, along with advanced manufacturing technology, ensuring stable and reliable product performance, complete functions, high automation, and high testing efficiency. It is a leading product in the domestic relay protection and high-voltage insulation industry for testing current transformers (CT) and voltage transformers (PT).

The Transformer Volt-Ampere Characteristics Comprehensive Test Instrument is a fully automated CT and PT testing device. It can perform tests such as the CT and PT volt-ampere characteristic test, CT and PT polarity test, CT and PT ratio and polarity ratio test, automatic calculation of arbitrary point CT error curves, and analysis of CT/PT ratio discrepancies. The instrument can automatically collect, analyze, store, and print test data, and the data can also be stored on a USB drive.

Additionally, the monitor features an 8-inch color screen with a high resolution of 800x600, full-touch operation, and real-time display of test curves. This allows operators to immediately observe test results and identify any potential issues. The test report not only displays the test curve but also lists the test data in the preferred numerical order, including test time and print time, making it suitable as the original test data.

This product is ideal for field testing and calibration of various CTs and PTs due to its large output capacity and comprehensive functionality.  

The transformer short-circuit impedance tester uses a popular ARM processor with a 168MHz main frequency and 128MB of memory, which can be expanded with a 4GB memory card. The instrument features a 7-inch high-definition color touch screen and employs the EmWin display interface, making the user interface intuitive and easy to operate. It can be fully operated via the touch screen, eliminating the need for a keyboard.

The instrument supports a database and allows data export via a USB flash drive or transmission to a background computer through a data cable.

The circuit design of the instrument is both elegant and innovative, providing superior performance, powerful functionality, compact size, and lightweight construction. In addition to testing the impedance load parameters of the transformer, the instrument can also measure harmonic content and waveforms on-site. With its user-friendly operation, the instrument offers a reliable foundation for transformer parameter analysis.  

The Transformer LV Short-Circuit Impedance Tester is designed for use in LV load impedance testing during delivery, overhaul, trial tests, and handover tests of power transformers (both single-phase and three-phase).

It measures the short-circuit impedance (%) of the power voltage on-site and compares it with the value indicated on the nameplate or the factory default. This helps identify any defects, such as winding displacement or deformation, which may result from major failures during transportation, installation, or operation after the delivery test. (A significant change in short-circuit impedance is considered if it exceeds ±3%, as specified in the China International Conference on Electricity Distribution 2000 (“CICED 2000”)).

The Transformer LV Short-Circuit Impedance Tester does not require an external voltage regulator and uses a primary connection mode. Once the parameters are entered, the tester automatically begins the three-phase testing, calculates the impedance error percentage, and provides intuitive results. This is a rapid and efficient tester for detecting winding deformation in transformers on-site.

The transformer winding deformation tester is designed for power transformers with a voltage rating of 6 kV and above, as well as other transformers with special purposes. Power transformers are susceptible to various faults, such as short-circuit currents and physical collisions, during operation and transportation. These factors can subject the transformer windings to high electro-dynamic forces, which may lead to a loss of stability. Such forces can cause permanent deformations, including local distortion, swelling, or dislocation, all of which can severely affect the safe operation of the transformer.To measure the deformation of transformer windings, the frequency response analysis method is used, in accordance with the national standard DL/T 911-2004 for the electric power industry. This method involves detecting the amplitude-frequency response characteristics of each transformer winding and comparing the results vertically or horizontally. Any changes in the amplitude-frequency response characteristics are analyzed to identify potential winding deformations.

This instrument utilizes high-frequency detection technology to measure partial discharge and integrates several advanced technologies, including computer technology, ultrasonic and radio frequency sensing, transient waveform sampling, analog electronics, high-speed signal acquisition, and digital signal processing. Developed on the Linux operating system platform, it provides both 2D and 3D maps of partial discharge, amplitude-phase spectrum waveforms, and discharge signal quantification values.By observing and analyzing the partial discharge pulse waveform—either statically or dynamically—over a single or multiple cycles, this instrument can thoroughly evaluate the partial discharge condition of electrical equipment. It is particularly suited for the routine inspection of the insulation performance of high-voltage cables, power transformers, and other electrical equipment.With its high sensitivity and strong adaptability, this instrument can effectively detect insulation defects and is an ideal tool for assessing the condition of power equipment during live operation.

Transformer DC resistance testing is essential during various stages of transformer manufacturing and maintenance, including factory testing of semi-finished and finished products, installation, overhaul, tap changer replacement, handover testing, and preventive maintenance in the power sector. This test helps evaluate the welding quality of winding joints, detect short circuits between turns, and verify the functionality of the voltage tap changer contacts. It also checks the alignment of the actual tap changer position with the indicated position, the integrity of lead wires, and the condition of multi-strand wires, including the detection of any breaks in the strands.The tester is controlled by a high-speed microprocessor, ensuring high automation with functions such as automatic discharge and discharge alarms. The instrument provides high test accuracy, is easy to operate, and allows for rapid measurement of transformer DC resistance, making it an indispensable tool for transformer testing.

The Sweep Frequency Response Analyzer is designed for power transformers with a voltage grade of 66kV and above, as well as other special-purpose transformers. During operation and transportation, power transformers are vulnerable to impacts from fault short-circuit currents or physical collisions. These conditions can cause the transformer windings to lose stability due to the powerful electro-dynamic forces exerted by the short-circuit currents. This may lead to permanent deformations, such as local distortion, swelling, or dislocation, all of which can severely affect the transformer's safe operation.To assess the deformation of transformer windings, the frequency response analysis method is used in accordance with the national standard DL/T911-2016 and IEC 60076-18 for the electric power industry. This method involves detecting the amplitude-frequency response characteristics of each transformer winding. The results are then compared either vertically or horizontally to identify potential deformation, based on changes in the amplitude-frequency response characteristics.

This Capacitance Inductance Tester is specifically designed to address the challenges in measuring high-voltage shunt capacitor banks in substations. It complies with national standards, including GB3983.2-1989 "High-voltage Shunt Capacitors," DL/T840-2003 "Technical Conditions for the Use of High-voltage Shunt Capacitors," and JB5346-1998 "Series Reactors". It is developed primarily for the measurement of high-voltage parallel capacitor banks and reactors used in reactive power compensation devices.The Capacitance Inductance Tester utilizes a high-speed microprocessor to simultaneously collect both the voltage signal and current signal from the tested components. It automatically calculates important parameters such as capacitance, inductance, and other related values. The on-site measurement of capacitors does not require disconnecting the wires, simplifying the testing process and significantly improving operational efficiency.After testing, the Capacitance Inductance Tester automatically calculates the capacitive value of each phase and other relevant parameters, enabling easy identification of capacitor quality changes and detecting potential faults in the connecting conductors between devices.

The Zinc Oxide Arrester Comprehensive Tester is used to check the electrical performance of zinc oxide arresters (MOAs). This instrument is suitable for on-site inspection of zinc oxide arresters at all voltage levels, as well as for factory testing and acceptance testing in the event of a power failure. By measuring parameters such as total current, resistive current, and others, it is possible to detect dangerous defects, such as internal insulation issues and valve aging in the zinc oxide arrester.

The HZ2613 Transformer Short-Circuit Impedance and No-Load Integrated Tester is the latest product launched by our company. The instrument uses a popular ARM processor with a 168 MHz main frequency and 128 MB of memory, expandable with a 4 GB memory card. It features a 7-inch HD color touch screen combined with the EmWin display interface, making the instrument user-friendly and easy to operate. The full touch-screen operation eliminates the need for a keyboard.
The instrument supports database functionality, and data can be exported via a USB drive or transferred to a background computer through a data cable.The circuit design of the instrument is highly refined, with a unique approach that provides superior performance, powerful functionality, compact size, and light weight. It can not only test the no-load parameters of the transformer but also measure the harmonic content and waveform. Additionally, the instrument can record transformer no-load test curves, providing a reliable basis for transformer fault analysis.

The lightning arrester is an important piece of electrical equipment in power networks, designed to protect power equipment from over-voltage. Normally, the operation of the arrester and the leakage current are monitored through an arrester monitor. However, due to poor sealing, the monitor may be exposed to water or moisture during operation, leading to internal component corrosion. In such cases, or for other reasons, the monitor's counter may fail to operate correctly, resulting in inaccurate leakage current readings. Therefore, according to The Regulations, the arrester monitor should be checked annually.
The reliability of the counter's operation is critical for the power system. It is an important parameter that records the number of lightning strikes received by the arrester during normal operation. This information provides a crucial basis for power system workers to inspect the arresters.

The handheld zinc oxide arrester tester is a specialized instrument used for field and laboratory testing of various electrical parameters of arresters. This instrument incorporates advanced technologies such as microcomputer sampling and control, and can measure parameters such as full current, third harmonic, resistive current, resistive current peak value, capacitive current, and active power of the zinc oxide arrester under power frequency voltage. It also displays the voltage and current waveforms and can print out test data.Equipped with a large-screen LCD display and Chinese-language menu prompts, the instrument enhances user interaction, making operation more intuitive. It also provides real-time waveform display on-site. The instrument features simple wiring, high measurement accuracy, and strong reliability. Its compact size, light weight, and integrated design make it easy to carry and operate in the field.

The Transformer Dielectric Loss Tester is a fundamental method for insulation testing that effectively detects overall damp deterioration and local defects in the insulation of electrical equipment. It is widely used in electrical manufacturing, equipment installation, handover, and preventive maintenance testing. Measuring the dielectric loss of transformers, mutual inductors, reactors, capacitors, bushings, and lightning arresters is a basic technique for assessing their insulation performance.
The dielectric loss tester has overcome the limitations of traditional bridge measurement methods by adopting frequency conversion power supply technology. It uses a microcontroller and modern electronic technology for automatic frequency conversion, mode/number conversion, and data processing. The tester features strong anti-interference capabilities, fast testing speed, high precision, automatic digitization, and easy operation.
The power supply uses a high-power switching unit that outputs pure sinusoidal waves at 45Hz and 55Hz. It also includes automatic voltage regulation, providing up to 10 kV of voltage. The tester automatically filters out 50Hz interference, making it suitable for large field tests in environments with high electromagnetic interference, such as substations.

The Transformer Dielectric Loss Tester is widely used in the power industry for testing transformers, mutual inductors, bushings, capacitors, lightning arresters, and other electrical equipment.

In the manufacturing process of transformers, including semi-finished product testing, factory tests for finished products, installation, overhauls, tap changer adjustments, handover tests, and preventive tests as required by the power department, it is necessary to measure the DC resistance and transformation ratio of the transformer. This testing can check the welding quality of winding joints, detect inter-turn short circuits in the winding, verify the contact quality of each position of the voltage tap changer, and ensure that the actual position of the tap changer aligns with the indicated position. It also helps identify issues like stock breaks.

Traditional testing methods require multiple wiring setups and interval tests using two separate instruments, which is time-consuming and inefficient, significantly delaying production progress.

To address the need for faster measurements of DC resistance and transformation ratios in transformers, our company has developed the HZ2162 DC Resistance and Transformer Turns Ratio Integrated Tester. This instrument features a one-time wiring setup, allowing both the transformation ratio test and high/low six-phase DC resistance tests to be completed without disconnecting the wires. All functions can be easily accessed and operated through a touch screen.