Fluke 1623 Basic GEO Earth Ground TesterThe Fluke 1623 is perfect for performing predictive maintenance checks of commerical and industrial applications. The Fluke 1623 is an all in one earth ground tester, offering 'one button' simplicity. Not only measure ground resistance using the classic 'fall of potential test' but also enable time saving testing using the 'selective' and 'stakeless' methods. 'Selective' testing does not require the electrode under test to be disconnected during the