For years, we have sailed without it and didn’t even know the problem. The European Committee for Standardization has presented a directive that requires the protection conductor to be connected to the negative DC grounding of the yacht. Due to the connection between the protective conductor and the negative DC grounding, a galvanic balance may occur between the neighboring yacht, the marina or other structures in the water and one’s own boat.
If your own yacht is well protected by anodes, they will provide protection via the power plug for all those who do not use anodes. If your own anodes are used up or insufficient, corrosion can cause serious damage to the underwater hull, engine, valves, and hull.
The solution is twofold. Either one does without shore power or uses this only briefly (plug pull!) or one uses an isolating transformer and/or a galvanic isolator.
The Allpa galvanic insulator installed in ATHENE raises the threshold voltage to 1 Volt by means of diodes. This ‘barrier’ is high enough to interrupt the potential difference between metals: the anodes protect your own ship. Higher voltages such as 230 volts flow unhindered and do not interfere with the function of the protective conductor.