The Fluke 1623-2 GEO Earth Ground Tester measures earth ground loop resistances using only clamps with the stakeless test method. Two clamps placed around the earth ground rod eliminate the need for auxiliary stakes, leaving the bonded earth ground system intact during testing. This method is ideal for buildings with bonded earth ground systems.

Additional test methods include 3 and 4 pole fall-of-potential, 4 pole soil resistivity testing, and selective testing. The IP56-rated tester is suitable for outdoor use, with a turn and start one-button concept for instant measurement. Operating temperature range is 14 to 122°F (-10 to 50°C), and internal memory stores up to 1500 records.