HP 870 Installation Manual page 21

Figure 18 Grounding the device with the rack (2)
Grounding the device with a grounding conductor buried in the earth—If earth is available at
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the installation site, hammer a 0.5 m (1.64 ft) or longer angle iron or steel tube into the earth to
serve as a grounding conductor. Weld the yellow-green grounding cable to the angel iron or
steel tube and treat the joint for corrosion protection.
Figure 19 Grounding the device by burying the grounding conductor into the earth
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2
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