Common faults and troubleshooting methods of grounding resistance tester:

(1) The pointer of the meter head does not move, including checking the battery voltage and the measurement of the ground resistance tester. The cause of the failure is caused by the burnt of the meter head or the disconnection of the connection meter head and the circuit board. Open the meter head panel and move the pointer by hand. If the pointer cannot return to zero automatically, it indicates that the meter head has been shaken; otherwise, the meter head is welded. Measure the meter head with the resistance file of a multimeter. An open circuit indicates that the meter head is burned out. Then use the multimeter's current and voltage file to measure the original connection meter head connector, press the ground resistance meter to check the voltage button, if the multimeter has a voltage indicator, it indicates that the meter failure is caused by the damage of the meter head, and it can be repaired after replacing the new meter head; if the meter head is intact, Open the case of the instrument again, check the connection of the meter head, if disconnected and connected. The cable AC withstand voltage test device is suitable for the AC withstand voltage test of 10kV, 35kV and other cables. The cable AC withstand voltage test device is mainly composed of a variable frequency power supply (host), an excitation transformer, a resonance reactor, and a capacitor divider.

Such failures are usually caused by excessive vibration during the use or transportation of the instrument. Therefore, the grounding resistance measuring instrument should be protected from vibration during use and transportation to avoid unnecessary damage.

(2) Check that the battery voltage is normal and the grounding resistance cannot be measured. This failure is usually caused by the failure of the switching power supply, AC/DC conversion, and constant current output. Use a frequency meter to measure the C port. If there is no 820Hz AC output, you can check this part of the circuit step by step, find the faulty part from the output transformer, switch tube, oscillating circuit, etc., and replace it with new parts.

(3) Check that the battery voltage is normal and the measurement data is inaccurate when the ground resistance is measured, and the error is large. This fault is usually caused by the detection signal filtering and effect adjustment circuit failure, usually caused by the damage of the filter inductor T1, which can be repaired by replacing the T1 inductor.

(4) When the ground resistance measuring instrument is measuring, the measurement data fluctuates and the time is inaccurate. This phenomenon is usually fault-free. The problem is caused by the poor connection between the resistance meter and the ground stake (auxiliary electrode) and the measured grounding body. There are usually three connecting wires that are disconnected or the joints are loose, resulting in poor conductivity. If the wire is found to be disconnected from the joint metal pieces at both ends during use, it must be re-soldered with solder to ensure the normal measurement work of the instrument.