BoatHowTo · video

What this video covers

A single galvanic isolator can protect a boat with dual shore power inputs, provided the unit and the grounding conductors are sized to handle the combined maximum fault current of both circuits. When paralleling two 30-amp shore power circuits through one isolator, the grounding wire and the isolator must be upsized to accommodate a potential 60-amp fault. While the grounding circuits connect at the isolator, the hot and neutral wires must remain electrically separate to maintain two independent AC systems on board. If a boat owner chooses to parallel these circuits to a single shore power source, mechanical interlocks on the breakers are required to prevent both shore power inlets from being energized simultaneously. This configuration allows for load management when dock power is limited, though it requires careful attention to total amperage to avoid tripping breakers. Proper sizing of the grounding conductor and the isolator is essential for safety when combining multiple shore power inputs.

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