Enviraj Consulting
Soil Resistivity Testing
| Soil Resistivity Test | |
|---|---|
| Overview | Soil resistivity testing measures the capacity of the ground to pass an electrical current. This property is utilised in the electrical power industry for assessing the design requirements of earthing systems. |
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| How Does it Works | The Wenner 4-point Method is by far the most used test method to measure the resistivity of soil. Other methods do exist, such as the General and Schlumberger methods, however they are infrequently used for grounding design applications and vary only slightly in how the probes are spaced when compared to the Wenner Method. Standard soil resistivity testing procedure involves four equidistant electrodes set-out in a fixed configuration array, as shown in image above. A low frequency electrical current is applied across the outer electrodes and the voltage is measured between the inner potential electrodes. The resulting soil resistance reading is subsequently converted by standard equations into a resistivity reading. This value represents the average resistivity of the ground between the potential electrodes. Depth readings are acquired by electrical soundings using an expanding electrode array which is centred on the same point. The depth penetration achieved by individual resistivity readings increases in direct proportion to the electrode spacing of the array. |
| Test Parameters | Soil Resistance, Soil Resistivity |
| Testing Time | 2-3 hrs |
| Accuracy | - |
| Area of Application | Earthing System Design |
| Surveying Cost | ₹6,000-15,000/day |
| Precautions | - |
| Data Sources: | https://www.geophysical.biz/soil-resistivity.htm |
