By hvhipot 
The grounding resistance tester under HV Hipot Electric Co., Ltd. power can help many power workers conduct various power tests more conveniently.
When measuring grounding resistance, some factors can cause inaccurate grounding resistance:
(1) The soil composition around the grounding network is inconsistent, the geology is different, the density and dryness are different, and it has dispersibility The stray currents on the surface, especially overhead ground wires, underground water pipes, cable sheaths, etc., have a special impact on testing. Big one. Solution: Measure at different points and take the average.
(2) The direction of the test line is incorrect and the distance is not long enough. Solution: Find the testing direction and distance.
(3) The resistance of the auxiliary grounding electrode is too high. Solution: Sprinkle water on the ground stake or use a resistance reducer to reduce the grounding resistance of the current rod.
(4) The contact resistance between the test clip and the grounding measuring point is too high. Solution: Use a file or sandpaper to polish the contact points, and use a probe clip to completely clamp the polished contact points.
(5) The impact of interference. Solution: Adjust the pay off direction, try to avoid directions with high interference, and reduce instrument readings.
(6) Instrument usage issues. Low battery level, solution: replace the battery.
(7) The accuracy of the instrument has decreased. Solution: Recalibrate to zero.
The accuracy of the grounding resistance test value is one of the important factors in determining whether the grounding is good. Once the test values are inaccurate, it will either waste manpower and reseries resonances (measurement values are too large), or pose a safety hazard to the grounding equipment (measurement values are too small).