The DC resistance fast tester (micro-ohmmeter) is a high-precision replacement product for DC single and double arm bridges. The DC resistance fast tester adopts advanced switching power supply technology and displays measurement results on a dot-matrix LCD, overcoming the disadvantage of LED displays that are difficult to read in sunlight, and also features automatic arc suppression. DC resistance testing of transformer windings is an essential test item after transformer handover, major repairs, and tap changer changes. In general, using traditional methods (bridge method and voltage drop method) to measure the DC resistance of transformer windings and high-power inductive equipment is a time-consuming and labor-intensive task. To change this situation, shorten measurement time, and reduce the workload of test personnel.

The DC resistance tester is also known as DC resistance measuring instrument, DC resistance meter, transformer DC resistance tester, DC resistance detector, DC digital bridge, etc.

Overview: DC resistance testing is an essential test item after transformer handover, major repairs, and tap changer changes. In general, using traditional methods (bridge method and voltage drop method) to measure the DC resistance of transformer windings and high-power inductive equipment is a time-consuming and labor-intensive task. To change this situation, shorten measurement time, and reduce the workload of test personnel, the DC resistance fast tester was developed. With a high-speed microcontroller as the core, built-in rechargeable battery and charging circuit, and adopting high-speed A/D converter and programmable current source technology, it achieves unprecedented measurement results and highly automated measurement functions, with high accuracy, wide measurement range, stable data, good repeatability, strong anti-interference capability, and complete protection functions. It features fast charge and discharge. The instrument is small in size, light in weight, and easy to carry. It has the characteristics of rapid measurement, convenient use, and high measurement accuracy. The self-check and automatic calibration functions reduce the difficulty of instrument use and maintenance, making it an ideal device for measuring the DC resistance of transformer windings and high-power inductive equipment.

The DC resistance tester measurement current is usually: 1A, 3A, 5A, 10A, 20A, 30A and other different measurement gears. The instrument consists of a constant current power supply and a voltage signal detection part, with five-digit LCD display. The output current gear is adjustable, suitable for DC resistance measurement of various small and medium-sized transformers.

Transformer DC resistance measurement is a mandatory test item in transformer manufacturing for semi-finished and finished products, factory acceptance tests, installation, handover tests, and preventive tests in power departments. It can effectively detect manufacturing defects such as poor material selection, welding issues, loose connections, missing strands, broken wires in transformer coils, and hidden dangers after operation.

The DC resistance tester is a new generation of transformer DC resistance testing instruments. It can automatically select the test current according to different types of power transformers and display the test results at the fastest speed. The DC resistance tester also has storage, printing, discharge indication and other functions. It has a built-in non-volatile memory that can save measurement data for a long time. The adoption of a liquid crystal display gives the instrument a good human-machine interface, making it the preferred equipment for DC resistance testing work.

The DC resistance tester is a high-precision, wide-range resistance tester controlled by a high-performance microprocessor. It can test resistances from 1μΩ to 3MΩ, with a maximum display of 30,000 counts. The highest test speed is 60 times/second. At a test speed of 15 times/second, it can still guarantee an accuracy of 0.05%, and the reading fluctuation can be controlled below 3 digits. It comes standard with temperature compensation function for precise resistance testing. Three current modes can meet various demanding resistance testing requirements.

The transformer DC resistance tester is a new instrument designed for measuring the DC resistance of large-capacity transformers. It consists of a high-precision constant current power supply and a test part integrated into one unit. The test process is controlled by a microcomputer, automatically completing constant current judgment, data acquisition, data processing, resistance display, and printing.

The DC resistance tester is a high-precision replacement product for DC single and double arm bridges. The instrument adopts advanced switching power supply technology, and its measurement speed is more than a hundred times faster than that of bridges. The display part uses a four-and-a-half-digit LCD to show measurement results, and a three-and-a-half-digit LCD to show ambient temperature or test current value, overcoming the disadvantage of LED displays that are difficult to read in sunlight, and also features automatic arc suppression. This instrument has the advantages of fast measurement speed, high accuracy, intuitive display, strong anti-interference capability, small size, low power consumption, stable and reliable test data, and is not affected by human factors. The instrument has a built-in rechargeable battery pack (12V), supports both AC and DC power, and is convenient for on-site and field testing.