Intelligent Loop Resistance Tester is designed according to the latest power execution standard DL/T845.4-2004 of the People's Republic of China, combining high-frequency switching power supply technology and digital circuit technology. The intelligent loop resistance tester is suitable for measuring the loop resistance of switch control equipment. Its test current adopts the national standard recommended DC 100A and 200A. The loop resistance can be directly measured at currents of 100A and 200A, and the final test results are displayed on a large-screen LCD, with functions such as data storage, output printing, and time setting. Additionally, 50A and 150A gears are available for user selection. This instrument has accurate measurement and stable performance, meeting the requirements of on-site high-voltage switch maintenance and loop resistance testing in high-voltage switch factories for power and power supply departments.
- Chinese Name
- Intelligent Loop Resistance Tester
- Equipment Use
- High-precision measurement
- Performance Features
- High stability
- Resolution
- 0~99.99, 0.01μΩ
Table of Contents
- 1 Product Overview
- 2 Equipment Use
- 3 Performance Features
- 4 Technical Indicators
- 5 Fault Phenomena and Troubleshooting
- 6 Precautions
- 7 Packing List
- 8 Basic Knowledge
Intelligent Loop Resistance Tester
When measuringthe contact resistance of the conductive circuit of high-voltage switches, due to the influence of oil film and oxide layer between contacts, the measured value is several times larger, unable to truly reflect the contact resistance value. Therefore, the Ministry of Electric Power standard SD301—88 "AC 500kV Power Equipment Handover and Preventive Test Procedures" and the new version of "Preventive Test Procedures for Power Equipment" stipulate that the measurement current for contact resistance of circuit breakers and disconnectors shall not be less than DC 100A to ensure accurate test results.
Intelligent Loop Resistance Tester Currently, the conventional QJ44 double-arm DC bridge is commonly used in power systems to measure contact resistance, but the test current of such bridges is only at mA level, making it difficult to detect defects such as reduced cross-sectional area of loop conductors. When measuring the contact resistance of high-voltage switch conductive circuits, due to the influence of oil film and oxide layer between contacts, the measured value is several times larger, unable to truly reflect the contact resistance value. Therefore, the Ministry of Electric Power standard SD301—88 "AC 500kV Power Equipment Handover and Preventive Test Procedures" and the new version of "Preventive Test Procedures for Power Equipment" stipulate that the measurement current for contact resistance of circuit breakers and disconnectors shall not be less than DC 100A to ensure accurate test results.
Equipment Use
The intelligent loop resistance tester is suitable for high-precision measurement of contact (loop) resistance of high-voltage switches, and is also applicable to other occasions requiring large current and micro-resistance measurement.
Performance Features
The intelligent loop resistance tester has high current: using the latest switching power supply technology, it can continuously output large current for a long time, overcoming the drawbacks of instantaneous current in pulse power supplies, effectively breaking down the oxide film on switch contacts, and obtaining good test results.
High stability: under severe interference conditions, the last digit of the LCD can stabilize within ±1 digit, with stable readings and good repeatability.
High precision: using dual-channel high-speed 16-bit Σ－Δ AD sampling and the latest digital signal processing technology, the highest resolution reaches 0.01μΩ, making it the only contact resistance tester in China that can achieve 0.01μΩ resolution with high stability, surpassing imported large-current micro-ohmmeters in performance.
Intelligent: using imported high-performance CPU, the system automatically switches ranges based on signal strength during measurement, ensuring the accuracy of the product. The over-temperature protection circuit can automatically stop output current when the instrument exceeds the set temperature, ensuring safe use.
High quality: key components are all imported, and the cleverly designed temperature compensation circuit effectively eliminates the influence of ambient temperature on measurement results. The use of military-grade connectors enhances vibration resistance.
Powerful functions: current can be freely selected between 50A and 100A, and test time can be set arbitrarily from 5s to 599s, overcoming the shortcomings of other similar instruments that cannot set measurement time or have too short continuous working time, far exceeding the performance of other similar instruments.
Friendly human-machine interface: data input via rotary mouse is convenient and fast, allowing users to set the instrument date and time, save measurement data in real-time, and print measurement results immediately.
Multiple communication methods: can communicate with computers via RS232 serial port (9-pin) or USB data cable, uploading measurement data to the computer for further analysis and processing by test personnel.
(9) Easy to use: small size, light weight, and portable.
