There is an increasing awareness in the electrical indu […]
There is an increasing awareness in the electrical industry of the benefits of a low-resistance, high-quality grounding system.
Copper-bonded, galvanized, and stainless steel ground rods are available in many different sizes. We will not focus on stainless steel rods as their high cost prohibits widespread use. More commonly used are copper-bonded and galvanized steel ground rods.
Besides price, what really makes these rods different? Both rods are composed of a steel core with a tensile strength ranging from 58,000 psi for galvanized rods to >90,000 psi for copper-bonded steel rods.
From a theoretical standpoint, the higher the tensile strength, the less likely the rod is to “mushroom” or spread when being driven. This is a concern when rods are being coupled or when connections are being made to the top of the rod.
Practically speaking, we all know that any ground rod will mushroom if you hit it without using a drive sleeve specifically designed to prevent this. So, the steel used in a copper-bonded rod may give it a slight edge in “driveability,” but not enough to classify it as a superior electrode.