What is the minimum acceptable test voltage for a good sacrificial anode?

The minimum acceptable test voltage for a good sacrificial anode is typically 900 millivolts. This threshold is important because it indicates that the anode is still providing adequate protection against corrosion by maintaining a sufficient level of electrochemical potential.

When sacrificial anodes are tested, a reading below this level could suggest that the anode is either insufficiently reactive or has become ineffective due to depletion or coating by corrosion products. The 900 millivolts value serves as a benchmark, providing assurance that the anode still possesses effective cathodic protection capabilities necessary for prolonging the life of the structure it is meant to protect, such as pipelines or storage tanks.

Choosing a lower voltage, such as 400, 600, or 800 millivolts, may not adequately reflect the anode’s ability to protect against corrosion, leading to potential failures in the system being protected. Thus, adhering to the standard of 900 millivolts ensures optimal performance and safety in corrosion prevention strategies.