Marine Galvanic Isolation
Whenever your boat is connected to shore power, the hull and drive system are connected to the shore grounding system and to other adjacent vessels (also connected to shore power) via the grounding conductor in the shore power cable. This connection, while required for safety, creates a galvanic corrosion cell involving the dissimilar metals between boats and between a boat and the shore grounding system putting your boat at risk.
Boat owners can virtually eliminate this galvanic corrosion problem by inserting an appropriately rated and certified Galvanic Isolator in series with the grounding conductor of the ship-to-shore power cable. The function of the Galvanic Isolator is to provide AC continuity of the grounding conductor (required for safety in the event of an AC fault) and to simultaneously block the flow of corrosion-causing galvanic current.