The testers can alert you of reduced battery. This tends to preserve you from inaccurate readings by preventing readings when the facility is just too lower. Many of the testers can be calibrated to only one calibration level. The SCHLUMBERGER method is well suited for measuring soil resistivity

Relationships amongst electrical resistivity, compaction problems, hydraulic conductivity, and index Homes are noted for 10 soils that were utilized for constructing compacted soil liners… Though this probe doesn't have polarization effects, it does contain the fringe field influence.