The advantages of the measurement principle of the ground resistance tester method are: First, the operation is simple. The test can be performed without disconnecting the power supply of the device under test, and it is not necessary to insert the measuring probe or to separate the electrode under test. The grounding resistance can be measured by clamping the grounding conductor with a pair of clamps. The second is high precision. Its accuracy can reach 0.01Ω. The third is strong anti-interference ability. Various power frequency harmonics can be filtered out. Fourth, it can be used as a supplement to the way of piling. Under many conditions (such as dense houses or areas covered with cement), it is difficult or even impossible to measure the grounding resistance by piling. The principle of double-jaw testing can be used to measure the grounding pegs. The disadvantage of this measurement principle is that it cannot directly measure a single-point grounding system. Clamp ground resistance meters should be used with caution in single-point grounding systems.

The measurement principle is briefly described as follows: This meter is equipped with two jaws: voltage clamp and current clamp.

Double clamp ground resistance tester adopts digital processing technology, 4-wire method, 3-wire method and simple 2-wire method, selection method, double clamp method to measure ground resistance, large-diameter current clamp design, can measure the grounding using large-scale down conductor The system can flexibly and accurately measure any grounding resistance value in various complex grounding situations such as single-point and mesh grounding. There is no need to disconnect any parallel grounding electrodes during parallel grounding measurement, which greatly improves the convenience of measurement. Imported FFT (Fast Fourier Transform) technology, AFC (Automatic Frequency Control) technology, with unique anti-interference ability and environmental adaptability, repeated testing consistency is strong.