ZWHR-200C Contact Resistance Tester

• High stability, high precision.
• Friendly human-machine interface.
• Easy to use: small size, light weight, easy to carry.
• USB transfer

Company Profile

The company specializes in the research anddevelopment, production, sales, and service of electric power systemautomation testing equipment, providing customers with one-stopservices.

Product Introduction

At present, the conventional QJ44 double-arm DC bridge is commonly used in power systems to measure contact resistance. However, the test current of this type of bridge is only mA level, making it difficult to find the defect of reduced cross-sectional area of the loop conductor. When measuring the contact resistance of the high-voltage switch conductive circuit, due to the influence of the oil film and oxide layer between the contacts, the measured value is several times larger and cannot truly reflect the contact resistance value. To this end, the latest Ministry of Electric Power standard DL/T845.4-2004 “General Technical Conditions for Resistance Measuring Devices: Loop Resistance Tester” and the new version of the calibration regulations JJG1052-2009 “Calibration Regulations for Loop Resistance Testers and Direct Resistance Meters” make measurements ( The measurement current of contact resistance of isolation switches, circuit breakers, etc. shall not be less than DC 100A, and the minimum current maintenance time shall not be less than 60S to ensure accurate test results. The operation panel of this instrument adopts ergonomic design and conforms to operating habits. It adopts high-frequency switching power supply and digital circuit technology, and is suitable for measuring the loop resistance of switch control equipment. The test current adopts DC 100A and 200A recommended by national standards. The loop resistance can be directly measured at DC 100A and 200A. The test results are displayed on a large-screen LCD and have functions such as data storage, output printing, and time setting. There are also 50A and 150A gears for users to choose; customizable The test time, the maximum setting time is 599S, which is longer than the 60S specified by the standard; it is the only contact resistance tester in China that can reach 0.01μΩ resolution and is very stable, and its performance exceeds that of imported high-current microohmmeter. It complies with the requirements of on-site high-voltage switch maintenance and high-voltage switch factory loop resistance testing of electric power and power supply departments.

Functional Characteristics

1. Large current: Using the latest switching power supply technology, it can continuously output large current for a long time, overcoming the shortcomings of instantaneous current of pulse power supply, and can effectively break down the oxide film of switch contacts and obtain good test results.
2. High stability: Under severe interference conditions, the last digit of data on the LCD screen can be stable within the range of ±1 word, with stable readings and good repeatability.
3. High precision: Using dual-channel high-speed 16-bit Σ-ΔAD sampling and the latest digital signal processing technology, the highest resolution reaches 0.01μΩ. It is currently the only contact resistance tester in China that can reach 0.01μΩ resolution and is very stable. Its performance exceeds Imported high current microohmmeter.
4. Intelligent: Imported high-performance CPU, the system automatically switches the range according to the signal size during measurement to ensure the test accuracy of the product. The over-temperature protection circuit can automatically stop the output current when the instrument exceeds the set temperature to ensure the safe use of the instrument.
5. High quality: All key components are imported. The cleverly designed temperature compensation circuit effectively eliminates the impact of ambient temperature on the measurement results. The use of military connectors enhances the anti-vibration performance.
6. Powerful functions: the current can be freely selected among 50A, 100A, 150A and 200A, and the test time can be set arbitrarily between 5s and 599s, overcoming the shortcomings of other similar instruments that cannot set the measurement time or the continuous working time is too short. Far exceeds the performance of other similar instruments.
7. Friendly human-machine interface: input data by rotating the mouse, which is convenient and fast. You can independently set the date and time of the instrument, save the measurement data in real time, and print the measurement results instantly.
8. USB transfer: The measurement data can be transferred to a U disk through the USB interface, and the measurement data can be further analyzed and processed with the host computer software.
9. Easy to use: small size, light weight, easy to carry.

Technical Parameter

Product Detail