Soil Electrical Resistivity/Conductivity or ground Earth Resistance is measured with a Megger Earth/Ground Tester using the Wenner Alpha 4 electrode equal spacing method. A pre test ground voltage check reduces errors and the test resolution is 0.01 Ω and up to maximum of 200 kΩ.
A number of measurements can be made, each along a transect at varying spacings (depths) to characterise the strata to over 100 m depth. We assess ground temperature and moisture and the survey in general conforms to:
National Grid Company Directive (2022)
STANDARD TECHNIQUE: TP21OA
Earthing System Measurements – Part A, Soil Resistivity
Typical sites we work on are the jointing bay locations for HVDC power cables, solar array sites or proposed substation locations within a development. A survey point may typically consist of around six spacing (depth) variations to 30 m depth with transects at right angles to each other.
