Product Overview：

​In modern power systems, conventional QJ44-type dual-arm DC bridges are widely used to measure contact resistance. However, these bridges employ milliampere-level test currents that fail to detect defects caused by reduced conductor cross-sectional area in circuits. When measuring contact resistance in high-voltage switchgear circuits, measurement values can be several times higher than actual values due to interference from oil films and oxide layers between contacts, making them unreliable indicators of true resistance. To address this, the latest standard DL/T 845.4-2004 "General Technical Requirements for Resistance Measuring Devices: Circuit Resistance Testers" and the updated verification specification JJG 1052-2009 "Verification Specifications for Circuit Resistance Testers and DC Resistance Meters" require that measurement currents for contact resistances in switches, isolators, and circuit breakers must not be less than 100A DC with a minimum holding time of 600 seconds, ensuring accurate test results.

This instrument features an ergonomic control panel designed for user-friendly operation. Utilizing high-frequency switching power supplies and digital circuit technology, it is specifically engineered for measuring circuit resistance in switching control equipment. The test current complies with the national standard-recommended DC 100A. Capable of directly measuring circuit resistance at 100A DC, the device displays test results on a large TFT color LCD screen. Key functions include data storage, print output, and time settings, with selectable amperage ranges: 100A,80A,50A,30A, and 10A. Users can customize test durations up to 600 seconds. As a highly stable contact resistance tester, its performance surpasses imported high-current microohmmeters. Designed for field maintenance of high-voltage switches in power supply departments and circuit resistance testing at switchgear manufacturers, this instrument meets stringent industry standards.


Technical parameters: ​ ​

Measurement range: 0-250mΩ

Minimum resolution: 0.001 μ Ω

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

Test power supply: constant current limited voltage, approximately 8.0V

Test current: DC 10A, 30A, 50A, 80A, 100A

Test current accuracy: ± 5%

Measurement time: 5-600 seconds can be set

Bluetooth communication: using Bluetooth communication method to connect with the digital protocol of State Grid Corporation of China

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

Data storage: Store 100 sets of measurement data

Working environment: Temperature -10~50 ℃, humidity ≤ 90%

Host weight: approximately 5.2kg (excluding cables)

Host volume: 320mm × 255mm × 175mm