Cathodic protection system

Cathodic protection system (CPS) is used to reduce corrosion by minimizing the difference in potential between anode and cathode. This can be achieved by applying a current to the structure to be protected from electrical source. When enough current is applied, the whole structure will be at one potential, thus anode and cathode sites will not exists. CPS is commonly used on many types of structures such as pipelines, underground storage tanks, locks and ship hulls. The main objective of this work is to discuss and compares the two methods of applying cathodic protections by using an impressed current system and sacrificial anode. The physical models were also developed for the two methods. The importance of controlling the protective current in the system is presented and discussed. Calculated and measurement results for the two methods have been presented in this paper. Measurement of output current were taken each week showed that there is a decrease in the required current according to time due to reduced of anode surface during the life of the system.