Soil Resistivity Measurement
Soil Resistivity Measurement
(OP)
Client's specification calls for soil resistivity to be measured before and after backfilling if the thickness of back-fill exceeds 1m. Wonder why this should be done!? ![[ponder] ponder](https://www.tipmaster.com/images/ponder.gif)
Does this have any reference to IEEE 80 / 81? I am working is IEC area.
Thanks in advance!
If there is a separate forum, please advise re-direction.![[neutral] neutral](https://www.tipmaster.com/images/neutral.gif)
Rgds
![[ponder] ponder](https://www.tipmaster.com/images/ponder.gif)
Does this have any reference to IEEE 80 / 81? I am working is IEC area.
Thanks in advance!
If there is a separate forum, please advise re-direction.
![[neutral] neutral](https://www.tipmaster.com/images/neutral.gif)
Rgds






RE: Soil Resistivity Measurement
What depth is the grid going to be installed?
RE: Soil Resistivity Measurement
One practical problem is that the presence of ground grid conductors, buried metal pipes, rebar and foundations can all affect the soil resistivity measurement. It becomes difficult after construction to measure the soil resistivity because of the other objects in the soil. A soil sample can be sent to a lab for a measurement, but I never got good correlation between field measurements and lab results.
RE: Soil Resistivity Measurement
RE: Soil Resistivity Measurement
RE: Soil Resistivity Measurement
We just had a hell of a problem with a large feeder installation wherein the contractor instead of the concrete encasement specified, backfilled with sea sand, (native "soil"), and it turned out to have a thermal "Rho" of almost 400 Deg C-cm/watt, whereas the conductor ampacity tables in most code books are based on 90 Deg C-cm/watt. This resulted in excessive heating in the duct banks and premature feeder failure. And of course the inevitable, interminable and exasperating conversations with those of the legal ilk.
RE: Soil Resistivity Measurement