... pole earth resistance mearurement.*4 pole soil resistivity testing.*Current Clamp selection method is used to measuring earth resistance ... interference voltage.*Automatically measuring the interference voltage and the leakage current. The limited value will be alarmed.*Auto power off ... 0.02Ω~29.99Ω±(5%rdg+5dgt)Test Short Current≤250mASoil ResistivityVoltage:AC20/48VFrequency:94Hz,105Hz,111Hz,128Hz,AFC ...