Nothing is quite so common or abundantly available throughout the world as the earth’s soil. You are probably more apt to think of earth as something to be tilled for planting or to be excavated for a building foundation. Yet, it also has an electrical property — conductivity (or low resistance) — that is put to practical use every day in industrial plants and utilities.
“Earth resistance” is the resistance of soil to the passage of electric current. The earth is a relatively poor conductor of electricity compared to normal conductors like copper wire. If the area of a path for current is large enough, resistance can be quite low and the earth can be a good conductor. It is the earth’s abundance and availability that make it an indispensable component of a properly functioning electrical system.
Earth resistance is measured in two ways for two important fields of use:
1. Determining effectiveness of “ground” grids and connections that are used with electrical systems to protect personnel and equipment.
2. Prospecting for good (low resistance) “ground” locations, or obtaining measured resistance values that can give specific information about what lies some distance below the earth’s surface (such as depth to bed rock).
Megger offers top-end ground testers systems for design and soil surveys as well as built-tough, easy to use testers for field engineers.
Available for rent, lease, or purchase from Protec Equipment Resources. We are here to help you with your testing equipment needs.