A majority of electrical systems are grounded (connected to the earth) for economic, reliability, and safety reasons. Although alternate methods are allowed under certain conditions, the most common method of grounding secondary distribution systems is using a ground wire connected to a ground rod driven at least eight feet into the soil.
One of the many functions of the ground wire and ground rod is to protect the electrical components from lightning. When lightning strikes the electrical distribution system it will try to find a place to eventually move into the ground. Without purposely designed ground connections throughout the system the lightning may flash over to the ground anywhere in the system, resulting in a spectacular release of energy that can destroy equipment in an electrical system or within the customer facility. The customer ground wire and ground rod provide an easy path for lightning that hits the electrical system to quickly move into the earth rather than entering the customer’s premise. Ground wires and ground rods are also used on various types of equipment through the distribution system.