(18.104.22.168 Corrosion Resistance continued)
Galvanic Anode CP
These systems are also referred to as “passive” systems because they use only the energy inherent in the different materials to create the current flow
The current power output is limited the EMF differential between the steel tank and the material used for the anode
Magnesium and zinc are the common materials used for underground storage tank system
The most common and well-known application is the Steel Tank Institute sti-P3 tank.
Impressed Current CP
These systems are also referred to as “active” systems because they rely upon an outside source to create the current flow.
Although they provide a wide flexibility in design they can be easily tampered with if not properly secured in a vandal-proof enclosure.
Power can accidentally be turned off when circuit breakers are not properly labeled.