The presence of excessive negative elements accelerates corrosion of aluminum and lead structures because of the alkalinity of the environment brought about by the cathode. The alkaline conditions are also harmful to the coating systems and can cause loosening of the bonding of the coating. Hydrogen development at the cathode surface of the high strength steels can cause it to brittle and loose its strength. This can cause tremendous disaster on high strength steels.
Spark hazards caused by electric currents in hazardous areas must also be taken into serious consideration. Sacrificial anodes are self regulating and do not create conflict with the structure, but they must be periodically inspected to ensure supply of continued protection. This is where the important role of close interval surveys comes in.
Close interval surveys done at the cathodic periodic systems are very important to ensure that hazards are avoided in the protected structure. The presence of copper sulfate means corrosion in the structure and they are detected by the use of RTU Remote in the terminal unit.
A “stray current corrosion” phenomenon can happen when corrosion is increased on the auxiliary structure where the electric current is discharge to the electrolyte. An example is when a ship is anchored near a protected yacht, or a metal coated pipeline crossing another pipeline which is cathodic protected.