| Measuring Earth Resistance For Electrical Grounding Systems:  The simplest and somewhat misleading idea of a
good “ground” for an electrical system is a section of iron pipe
driven into the earth with a wire conductor connected from the pipe
to the electrical circuit. In many cases this is not a suitable low
resistance path for electric current to protect personnel and
equipment. A practical earth electrode that provides a low ground
resistance is not always easy to obtain. But from experience gained by others you can learn how to set up a reliable system and how to check the resistance value with reasonable accuracy. Earth resistivity has an important bearing on electrode resistance, as does the depth, size, and shape of the electrode. |