Figure 1-1. Grounding rod
a. The best grounding rod (electrode) is made of copper (nonferrous metal) and is at least 1/2
inch in diameter (Figure 1-2).
Figure 1-2. Copper grounding rod
b. A copper-coated, steel grounding rod is at least 1/2 inch in diameter (Figure 1-3).
Figure 1-3. Copper-coated, steel grounding rod
c. A solid-steel (ferrous metal) grounding rod is at least 5/8 inch in diameter (Figure 1-4).