Digital earth resistance tester

The DET2/2 is a four-terminal digital model designed to operate in the most difficult (and electrically noisy) of test environments and for use on large, critical ground systems. This model has an extra digit of resolution (to 0.001) on readings and includes an interference filter, test current control and, most importantly, adjustable test current frequency (105-160 Hz).
As a four-terminal unit, the DET2/2 can also be used to make earth resistivity measurements.