High Current DC Loop Resistance Tester

The operation panel of this instrument adopts an ergonomic design that conforms to operating habits. It adopts high-frequency switching power supply and digital circuit technology, and is suitable for measuring the circuit resistance of switch control equipment, especially suitable for contact resistance test for circuit breaker. The testing current adopts the DC 100A recommended by the national standard. The circuit resistance can be directly measured at a DC of 100A, and the test results are displayed on a large LCD TFT color screen with functions such as data storage, output printing, and time setting. There are 50A and 100A gears for users to choose from; Customized testing time, with a maximum set time of 600S, it is a very stable contact resistance tester with performance exceeding that of imported high current micro ohmmeters. Meet the requirements of on-site high-voltage switch maintenance and high-voltage switch factory circuit resistance testing by the power and power supply departments.

At present, the conventional QJ44 double arm DC bridge is commonly used in the power system to measure contact resistance, and the test current of this type of bridge is only mA level, making it difficult to detect the defect of reduced cross-sectional area of the circuit conductor. When measuring the contact resistance of the conductive circuit of high-voltage switches, the measured value is several times larger due to the influence of the oil film and oxide layer between the contacts, which cannot truly reflect the contact resistance value. Therefore, the latest Ministry of Electric Power standard DL/T845.4-2004 "General Technical Conditions for Resistance Measurement Devices: Circuit Resistance Testers" and the new version of the verification regulation JJG1052-2009 "Verification Regulation for Circuit Resistance Testers and Direct Resistance Meters" stipulate that the measured current for measuring the contact resistance of (isolation) switches, circuit breakers, etc. should not be less than 100A DC, and the minimum current maintenance time should not be less than 600S, to ensure the accuracy of the test results.

1.Measurement range: 0-50m Ω

2.Minimum Resolution: 0.001 μ Ω

3.Measurement accuracy: ± (reading × 0.5%+1 μ Ω)

4.Test power supply: constant current and voltage limiting, approximately 5.0V

5.Test current: DC 50/100A

6.Test current accuracy: ± 5%

7.Measurement time: fast, 10~600seconds, continuous testing optional

8.Special testing line: resistance<20m Ω

9.Charging power supply: Input 180V~240VAC, 50Hz/60Hz

10.Data storage: Store 100 sets of measurement data

11.Working environment: temperature -10~50 ºC, humidity ≤ 90%

12.Host weight: approximately 7kg (excluding cables)

13. Host volume: 420mm × 340mm × 200mm