Reasons and solutions for the large resistance of the grounding resistance measuring instrument:

Since the ground net is buried in the soil, the ground resistance is directly related to the soil composition, temperature and humidity. That is to say, the soil resistivity affects the magnitude of the ground resistance value. The soil resistivity is an important data for grounding network design. We can use a ground resistance tester to measure the resistivity of this piece of soil. If the soil resistivity is too large, we can improve the soil. Soil resistance reducers or water can be used to maintain the contact between the soil and the ground net.

The method of measuring the grounding resistance of the ground grid is also the main reason for the large resistance. When measuring, we should clearly know the length of the diagonal of the ground grid, because the measuring current line length of the earth grid grounding resistance tester is 3~5 times the length of the diagonal line of the ground grid, and the measuring voltage line is 0.618 times the current line. .

The rust on the ground pile is cleaned, and the buried depth is greater than 0.5 meters. At the same time, check whether the connection between the test line and the ground pile is conducted. The current test line and the voltage test line are connected to the instrument according to the specified length and discharged in parallel. The other end is connected to the two ground stakes. After the wiring is completed, the instrument can directly press the test key to measure the grounding resistance value. The instrument will automatically eliminate wiring errors when measuring on the quadrupole principle.

Good grounding is not only for safety, but also to prevent damage to electrical equipment. Good grounding will improve the reliability of the equipment and reduce the possibility of damage caused by lightning or fault current.