Use corrosion-resistant materials to ensure long, continuous operation:
- Copper and stainless steel are good.
- Stainless steel has better corrosion resistance than copper.
- Copper clad steel is cheaper than copper and commonly available in commercial rods.
- Hot-galvanized steel (with a minimum coating thickness of 60 µm) is cheap, and good especially in dry soil.
- Galvanized steel is cheap, but it is not practical in corrosive soil because the service life is short.
- Stainless or galvanized steel bars that are used in reinforced concrete foundations can be used as ground electrodes, providing they are galvanically connected to each other, preferably by welding.
- Round solid wires and sheet metal tapes that are 2 … 3 cm (0.8 … 1.2 in) wide are good in dry soil, but in corrosive acid, salty, or wet environment they need frequent maintenance and are short-lived.
|Do not use bare steel or aluminum in ground electrodes because of their fast corrosion.
If you use stranded cables, use a strand with a big enough diameter to resist corrosion damage. For standard dimensions, see Table 2.