Introduction
The UHV-H200A is a high-precision tester specifically designed for measuring the loop resistance of high-voltage switches, circuit breakers, and switchgear. The device employs high-frequency switching power supply technology and digital circuit technology, enabling accurate detection of micro-ohm level resistance in the main circuit and contacts of equipment through high-current DC testing. It provides reliable data support for installation acceptance, operation and maintenance, and fault diagnosis of power equipment.
The device complies with relevant testing requirements such as DL/T 845.4-2004. It features high measurement accuracy, good stability, strong anti-interference capability, compact size, and light weight, making it particularly suitable for use in substations, power plants, power equipment manufacturing enterprises, and industrial power distribution sites.
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Product fuunctions
Circuit breaker loop resistance testing
Used for measuring the contact resistance of the main circuit and contacts of high-voltage circuit breakers.
Micro-ohm level low resistance measurement
Measurement range: 1 to 1999 μΩ, with resolution up to 1 μΩ, meeting high-precision low resistance detection requirements.
High-current testing
Supports four test current levels: 50A / 100A / 150A / 200A, improving the stability and accuracy of loop resistance testing.
Contact condition detection
Can assist in determining whether there are issues such as poor contact, oxidation, wear, or loose connections in circuit breaker contacts and switchgear connection points.
On-site preventive testing
Suitable for substations, power plants, and power equipment manufacturing enterprises, used for equipment installation acceptance, routine maintenance, and preventive testing.
What is a circuit breaker resistance tester?
Circuit breaker resistance tester, also known as a loop resistance tester, contact resistance tester, or micro-ohmmeter, is a specialized test device used for measuring the contact resistance of the main circuit of a circuit breaker. It outputs a large current and measures the voltage drop to accurately calculate the resistance of the circuit breaker contacts and conductive loop, thereby determining whether the contact performance is satisfactory.
(1) High current: For latest power supply technology, the Micro Ohmmeter supplier can continuously output high current which overcomes the weakness of instantaneous current produced by pulsed power. It can effectively breakdown/puncture the oxide layer of the switches and then get precise results.
(2) Strong anti-interference ability: The last number of test data will stably show in the LCD screen only with ±1 error even in strong Interference situation.
(3) Long service life: All the precise resistances used in the tester can reduce the temperature's impact on the measurement results and military connectors can enhance vibration resistance.
(4) Convenience: Small size, light weight.
What are the application scenarios of a circuit breaker resistance tester?
Power systems: Installation acceptance, periodic maintenance, and preventive maintenance of circuit breakers and switchgear in substations and distribution stations.
Power generation enterprises: Operation and maintenance of equipment in thermal, hydro, wind, and photovoltaic power plants.
Electrical manufacturing: Production testing and factory inspection of circuit breakers, switchgear, GIS, and other equipment.
Industrial power distribution: Inspection and maintenance of power distribution equipment in industries such as factories, petrochemicals, metallurgy, and mining.
Fault diagnosis: Identifying poor contact, contact wear, loose connections, and other issues to prevent equipment overheating and failures.
פרמטרים טכניים
| טווח מדידה | 1~1999μΩ |
| פתרון הבעיה | 1mΩ |
| זרם בדיקה | DC50A、100A、150A、200AFour speed fixed output |
| דיוק | 0.5%±1ד |
| Way to work | The connection |
| לְהַצִיג | Three and a half LCD |
| ספק כוח | AC220V±10% 50Hz |
| סביבת עבודה | Temperature: -10℃ ~ 40℃, humidity: ≤80%RH |
| דימיון | 440(L)×410(W)×190(H)mm3 |
| מִשׁקָל | 8.7kg(excluding attachments) |
FAQ about circuit breaker resistance tester
1. What is a circuit breaker resistance tester, and why is contact resistance testing necessary?
Circuit breaker resistance tester manufactures uses the high-current DC injection method to measure the contact resistance of circuit breaker main contacts, disconnecting switches, and other conductive connection points. By detecting micro-ohm level resistance changes, it can promptly identify defects such as contact wear, oxidation, poor contact, or loose connections, thereby reducing the risk of overheating and ensuring long-term safe and stable operation of power equipment.
2. Why is high-current testing more accurate than ordinary multimeter measurements?
The contact resistance of circuit breakers is typically only tens to hundreds of micro-ohms, which cannot be accurately measured by an ordinary multimeter. circuit breaker resistance tester outputs a high current of 100A, 200A, or higher, and incorporates the four-terminal (Kelvin) measurement technique to effectively eliminate errors introduced by test leads and contact resistance, thereby delivering more stable and reliable test results.
3. Which equipment is most suitable for use with a circuit breaker resistance tester?
The circuit breaker resistance tester factory is widely used for contact resistance testing of high-voltage, medium-voltage, and low-voltage circuit breakers, GIS switchgear, disconnecting switches, busbar connection points, and large conductive connectors. It is suitable for various testing needs in substations, power utilities, power plants, industrial enterprises, and electrical equipment manufacturers during factory inspection, installation commissioning, and routine maintenance.
For pricing and availability, please contact us for the latest quotation based on your required configuration and order quantity. The UHV offers a practical and reliable solution for professional electrical testing, making it a suitable choice for utilities, contractors, manufacturers, and maintenance teams. Contact us to discuss your requirements, obtain a competitive price, and receive further information about delivery, warranty, and after-sales support.



































