How to use the ground resistance tester

　　How to use a ground resistance tester? We have sorted out the specific measurement steps and taught you how to use the ground resistance tester correctly.

　　1. Preparation

　　1. Read the instruction manual of the ground resistance tester carefully and be familiar with its structure, performance and usage.

　　2. Prepare all the tools and accessories needed for measurement. Wipe the instrument and grounding probe, especially the grounding probe. Be sure to clean the dirt and rust on the surface that affect the conductivity.

　　3. Disconnect the connection point between the grounding main line and the grounding body or the connection points of all grounding branches on the grounding main line to achieve the purpose of disconnecting the grounding body and making it an independent body.

　　Preparation is a crucial task before starting measurement. If these preparations are not done well, it is very likely that the measurement will not proceed smoothly or the measurement results will not be accurate enough.

　　2. Measurement steps

　　1. Insert two grounding probes into the ground at a distance of 20m and 40m from the grounding body respectively along the radial direction of the grounding body, with an insertion depth of 400mm.

　　2. Place the ground resistance meter flat near the grounding body, and then connect the wires. The wiring method is as follows:

　　① Use a short dedicated wire to connect the grounding body to the terminal "E1" of the grounding measuring instrument (three-terminal measuring instrument) or to the common terminal after short-circuiting C2 and "(four-terminal measuring instrument)

　　② Use a long dedicated wire to connect the measuring probe (current probe) 40m away from the grounding body to the connecting button "C1" of the measuring instrument.

　　③ Use the remaining length of the dedicated wire in the middle to connect the measuring probe (potential probe) at ⒛m away from the grounding body to the terminal "P1" of the measuring instrument.

　　3. After placing the ground resistance meter horizontally, check and make sure that the pointer of the galvanometer points to the center line. If it does not point to the center line, adjust the "zero adjuster" to make the pointer of the meter point to the center line.

　　4. Adjust the "magnification scale" (or coarse adjustment knob) to a large magnification, and slowly turn the generator handle so that the pointer begins to deviate. At the same time, rotate the "measuring 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), increase the speed of turning the handle to make the speed reach above 120r/min, and at the same time adjust the "measuring dial" so that the pointer points to the center line.

　　6. If the reading of the "measurement scale" is too small (<1) and it is difficult to read the accurate value, it means that the magnification scale is too large. At this time, you should adjust the "magnification scale" to a smaller multiple, re-adjust the "measurement scale" 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” reading × “measurement scale” reading.