The current output of a galvanic anode installation is typically much less than that which is obtained from an impressed current cathodic protection system. Galvanic anode installations tend to be used mostly on underground structures in applications where cathodic protection current requirements are small and where earth resistances are acceptably low. Magnesium anodes are available in a variety of shapes and sizes, bare or prepackaged with the most popular being the 17 lb. prepackaged anode. Short chunky shapes are suitable for low resistivity areas, but long slender shapes should be employed in higher resistivity areas. Zinc anodes are also available in many shapes and sizes.
Favorable environments are sea water and salt marshes.
Short chunky shapes are suitable for low resistivity areas, but long slender shapes should be employed in higher resistivity areas. Aluminum anodes are not commonly used in earth burial applications. Some proprietary aluminum alloy anodes work well in a sea water environment. Self-powered so no external power source is required. Easy field installation.