For testing purposes, what specific type of current must a galvanic isolator block?

A galvanic isolator is designed to prevent galvanic current, which is a type of direct current that occurs when two different metals are in contact with an electrolyte in seawater, often leading to corrosion. This specific current can create unwanted electrochemical reactions that can damage metal components of a vessel over time.

The galvanic isolator effectively blocks these galvanic currents while allowing alternating current (AC) to flow freely for the proper function of electrical systems. This allows for the protection of the boat's metallic parts while ensuring that electrical systems remain operational. Understanding these details is crucial for maritime electrical systems, as the prevention of galvanic corrosion directly impacts the longevity and safety of the vessel's metal structures.