What Does Wenner 4-Point Test Method Mean?
Wenner 4-point test is a method of determining soil resistivity. The Wenner 4-point test method requires driving four spikes into the ground that have been arranged in a straight line and spaced equidistant. A known current is passed between the electrodes placed at the two ends known as the current probes. The potential difference is measured between the two middle spikes which take the soil resistance measurement and are known as the potential probes. Testing is carried out as close to the site as possible.
Poor quality reading may result if there is electrical interference which may cause unwanted signal to register in the meter or if metallic objects are present in the electrical path. Clearance between pins and other metallic structures in the vicinity should be at least equal to the pin spacing.