The method of using the ground resistance tester is as follows:

(1) Use the ground resistance tester to prepare for work

1) Familiarize with the instruction manual of the grounding resistance measuring instrument, and fully understand the structure, performance and method of use of the instrument.

2) Prepare the necessary tools and all instrument accessories for measurement, and wipe the instrument and the grounding probe clean, especially the grounding probe, be sure to clean up the dirt and rust stains on the surface that affect the conductivity.

3) Disconnect the connection point of the grounding trunk line and the grounding body or the connection points of all grounding branch lines of the grounding trunk line, so that the grounding body will be independent from any connection relationship.

(2) Measurement steps using grounding resistance tester

1) Insert the two grounding probes into the ground 20m and 40m away from the grounding body along the radiation direction of the grounding body, with a depth of 400mm.

2) Place the grounding resistance measuring instrument flat near the grounding body and connect the wires. The wiring method is as follows:

① Use the shortest dedicated wire to connect the grounding body to the terminal "E1" (three-terminal button measuring instrument) of the grounding measuring instrument or the common terminal (four-terminal button measuring instrument) shorted to C2.

②Connect the measuring probe (current probe) 40m away from the grounding body with the connection button "C1" of the measuring instrument with the longest dedicated wire.

③Connect the measuring probe (potential probe) ⒛m away from the grounding body with the terminal "P1" of the measuring instrument with the remaining special wire in the middle of the length.

3) After placing the measuring instrument horizontally, check whether the pointer of the galvanometer points to the center line, otherwise adjust the "zero adjuster" to make the pointer of the measuring instrument point to the center line.

4) Set the "magnification scale" (or coarse adjustment knob) to the maximum multiple, and slowly rotate the generator handle (the pointer starts to shift), and at the same time rotate the "measurement dial" (or fine adjustment Knob) to make the galvanometer pointer point to the center line.

5) When the pointer of the galvanometer is close to balance (the pointer is close to the center line), shake the handle faster to make the speed reach 120r/min or more, and adjust the "measurement dial" to make the pointer point to the center line.

6) If the reading of the "measuring dial" is too small (less than 1) and it is not easy to read and accurate, it means that the magnification scale is too large. At this time, you should set the "magnification scale" to a smaller multiple, readjust the "measurement dial" so that the pointer points to the center line and read the accurate reading.

7) Calculate the measurement result, that is, R ground = "magnification scale" number × "measurement dial" reading.