24 www.megger.comresistance is needed. This is where we come in with our Megger Ground Resistance Tester, a self-contained portable instrument that is reliable and easy to use. With it, you can check the resistance of your earth electrode while it is being installed; and, by periodic tests, observe any changes with time.To understand the principle of earth testing, consider the schematic diagram in Fig. 10a. Bear in mind our previous observation with reference to the earth shell diagram in Fig. 9: with increased distance from an Fig. 10: Principle of an earth resistance test(a)(b)
