AEMC 6422 User Manual page 25

Approximate Distance to Auxiliary Electrodes Using the 62% Method
Depth Driven
6 ft
8 ft
10 ft
12 ft
18 ft
20 ft
30 ft
2.3.1.4 Multiple Electrode System
A single driven ground electrode is an economical and simple means of making a
good ground system, but sometimes a single rod will not provide sufficient low
resistance, and several ground electrodes will be driven and connected in
parallel by a cable.
Very often when two, three or four ground electrodes are used, they are driven in
a straight line. When four or more are used, a hollow square configuration is
used and the ground electrodes are still connected in parallel and equally spaced
(see below).
Ground Tester Models 6422/6424
Distance to Y
45 ft
50 ft
55 ft
60 ft
71 ft
74 ft
86 ft
Distance to Z
72 ft
80 ft
88 ft
96 ft
115 ft
120 ft
140 ft
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