NRG USER MANUAL
SymphoniePLUS3 User Guide
SymphoniePLUS3_DataLogger_Manual
Rev. 17
support@nrgsystems.com | Page 60
31 December 2018
The NRG Grounding Kit will perform adequately in type 1 and 2 soils. For other soil types, or for
sites with a high incidence of lightning, you will need to augment the earth grounding system.
The best approach to grounding will depend on the soil type in your area. Soil resistivity is
directly related to moisture content and temperature. The colder it gets, the higher the
resistivity will be for a specific moisture content. Any moisture content below 20% quickly
increases ground resistivity exponentially to dangerous levels.
In most climates, moisture content and soil temperature change seasonally. During times of the
year when the soil is very dry or very cold, soil resistivity is at its highest, and getting a good
ground is more difficult. Keep this in mind when evaluating your site - it's better to put in too
much grounding than not enough.
You may want to consult a local utility regarding grounding techniques they've successfully used
in the site area.
Additional Notes
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Use longer ground rods, and/or install additional rods if needed.
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Cut the logger’s ground wire to the required length. Do not roll or coil any excess length of
ground wire.
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Additional contact surface helps, and soil conductivity improves with depth.
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If multiple rods are used, they must be installed far enough away from each other so that each
rod's effective resistance area does not overlap. NRG recommends a distance of 2 meters (~6.5‘)
between the grounding rods.
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Use high compression fittings at all conductor/rod connections.
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Use single strand, bare copper conductor wire with a thickness of at least 10 gauge.
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Ensure that the grounding rod(s) is free from non-conducting coatings such as paint or enamel.
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Wire all grounding rods together to provide electrical continuity.
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Where rock is encountered, drive the ground rod at a 45 degree angle, or bury it in a trench at
least 0.6 m (2 feet) deep (deeper is better; the key is to maximize the soil contact area).
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Protect the above-soil end of the rod and its electrical conductor attachment against damage.
Where the soil can become frozen, drive grounding rods below the frost line.
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Apply an anti-oxidation agent to all grounding connections.