8) Differences between the device Wenner and Schlumberger.
In the device Wenner distance between AM = BN is equal to MN, so doing increasing the distance between the electrodes A and B will also increase the distance between MN. However in the Schlumberger device is usually taken as the norm (for theoretical reasons) that the MN distance should be at most a fifth of the segment AB. Also a major drawback of the device Wenner is the need to move 4 electrodes simultaneously.
Another difference is that the curves for Schlumberger field device are superior to those of Wenner. The reason is that in the first remain fixed electrode potential, so that the surface effect which are embedded remains the same throughout the curve to the next junction. Now the device Wenner, as all the electrodes M and N are moving in each reading can be said that all stations are joint, and the jumps due to these on the entire curve, with no possibility of knowing, which is not in Schlumberger.