Product Introduction
The micro-ohmmeter developed by Wuhan UHV complies with the implementation standard DL/T 845.4-2004 of the People's Republic of China. It integrates high-frequency switching power supply technology with digital circuit technology, making it well-suited for measuring the contact resistance of switching control equipment.
The instrument operates at a DC test current of 100A, as recommended by the national standard, and directly measures circuit resistance under this current condition, displaying results digitally. With high accuracy and reliable stability, it meets the requirements for both high-voltage switch maintenance and factory-circuit resistance testing of high-voltage switches.
製品の特徴
1、High-Current Capability
Utilizing advanced switching power technology, the micro-ohmmeter delivers a sustained high-current output. This overcomes the limitation of transient pulse currents typical of conventional power supplies. The continuous high current effectively breaks through the oxide film on switch contacts, ensuring accurate and reliable test results.
2、Excellent Anti-Interference Performance
The instrument exhibits strong resilience against electromagnetic interference. Even in environments with significant interference, the last digit of the LCD readout remains stable within a range of ±1 count. This ensures stable readings and delivers excellent measurement repeatability.
3、Durable and Stable Design
Built for longevity and precision, the micro-ohmmeter employs high-accuracy resistors which minimize the impact of ambient temperature variations on measurement results. Furthermore, the use of military-grade connectors significantly enhances its robustness and resistance to vibration.
4、Portable and User-Friendly
Designed with field use in mind, the device features a compact form factor and light weight, making it highly portable and convenient for on-site testing.
|  |
技術的パラメータ
| 測定範囲 | 1～1999μΩ |
| 解決 | 1mΩ |
| 試験電流 | DC 6-100A |
| 正確さ | 0.5%±1d |
| Operating mode | 継続的 |
| ディスプレイモード | 3.5-digit LED display |
| 電源 | AC220V±10% 50Hz |
| 作業環境 | Temperature: -10℃~40℃, humidity: ≤80%RH |
| 寸法 | 390×300×150mm3 |
| 重さ | 6kg(excluding attachments) |
Significant product advantages
1. Ensure the safe operation of equipment: An increase in circuit resistance is the main cause of equipment overheating or even burning out. This instrument can directly detect this hidden danger and prevent it from developing into a major safety accident due to poor contact.
2. High precision and strong anti-interference ability: By using the DC voltage drop method (such as 100A constant current source), it can effectively overcome the interference of contact potential, accurately measure micro ohm level (μ Ω) resistance, and the results are reliable.
3. Improve operation and maintenance efficiency: The testing process is fast and simple, which can intuitively and quantitatively reflect the connection quality, provide accurate data support for status maintenance, avoid blind disassembly and excessive maintenance, and significantly improve work efficiency.
 |  |  |
Core application scenarios
1. Handover acceptance and preventive testing: Before the installation and operation of new equipment or during regular maintenance, measure the DC resistance of its conductive circuit and check whether the contact condition of the connecting parts is good. This is one of the most basic and important testing items for power equipment.
2. Evaluate the connection status and degradation trend: Through longitudinal comparison of previous test results, effectively discover the increasing trend of resistance caused by contact surface oxidation, looseness, contact electrical wear, etc., and timely warn potential faults.
3. Fault location and repair verification: When the equipment overheats or has insufficient current carrying capacity, it is used to accurately locate the specific connection point where the resistance abnormally increases, and verify the repair effect after maintenance.
Frequently Asked Questions (FAQ)
Q: What is the typical testing current of a contact loop resistance tester? A: The magnitude of the test current depends on the specific instrument design and the object being tested, usually ranging from tens to hundreds of amperes to ensure the accuracy and reliability of the test results. Wuhan UHV Power Technology Co., Ltd. has mature solutions in this area.
Q: Why does the resistance value of the circuit I measure fluctuate? A: This may be due to poor contact, incomplete breakdown of the oxide layer, or significant temperature changes during the testing process. It is recommended to clean the contact points before testing and choose a suitable testing method.
Q: Can circuit resistance testing replace infrared temperature measurement? A: The intelligent circuit resistance tester and infrared temperature measurement are complementary detection methods and cannot replace each other. Resistance testing directly measures the resistance value of a conductor, while infrared temperature measurement reflects the temperature during equipment operation. High resistance inevitably leads to heating, but heating may also be caused by other factors.
Q: What factors can affect the measurement accuracy of a contact loop resistance tester? A: In addition to the factors of the tested object itself, the accuracy level of the instrument, the quality of the testing cable, the ambient temperature, and the degree of standardization of the operator can all affect the measurement accuracy.
Q: What are the daily maintenance procedures for a contact loop resistance tester? A: Daily maintenance includes keeping the instrument clean, checking whether the testing cables are intact, and regularly conducting instrument self checks and calibrations.
