Overview Digital Ground Resistance Tester Rejects the traditional manual manual power generation method adopts advanced media and large scale integrated circuits, and uses DC / AC conversion techniques to combine the triple buttons and four-end button measurement modes with new ground resistors. . The working principle is that the DC / AC converter in the machine changes the DC constant current, and the circuit is formed by the auxiliary ground electrode C and the measurement object E, which generates an AC voltage drop on the measuring object, and feeds the AC amplifier through assist grounding. The electrode P amplified, and then multiplied by multiplying by multiplying by a power switch to display the instrument header head, you can get three different number limits 0 2 0 20 0 200