CPT G-TEST, User Manual

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The display will then show the soil resistivity value, as in the example below:
# = 620 @m
4_Pole a= 2m
To properly evaluate soil resistivity, measurements must cover the whole
area to be influenced by the grounding system. For an area of up to
10.000m², it is recommended to perform measurements in at least five
points, arranged as shown in the image below. Two sets of measurements
should be needed for the central point.
a
b
a/4
D
a/2
b/2
b/4
a/4
B
E
A
b/4
C
Measurements points: A, B, C, D & E
Direction of measurements: x & y
y
x
Larger areas can be divided in areas of 10,000m² each. In the case of dif-
ferent forms, limiting the area in smaller rectangles is a possible and practi-
cal solution.