BoatHowTo · video

What this video covers

Rapid depletion of zinc anodes at the dock typically indicates galvanic corrosion rather than stray current.2:04 Galvanic corrosion occurs when a boat lacks a galvanic isolator or isolation transformer, causing the vessel’s zincs to protect other metal objects or boats connected to the same shore power ground.2:04 Stray current corrosion, by contrast, involves a positive DC conductor fault that bypasses the zinc and causes rapid metal loss on the positive side of the circuit.0:53 Standard multimeters cannot accurately diagnose these issues while the boat is in the water.2:27 Accurate testing requires a silver-silver chloride half-cell lowered into the water to measure millivoltage across the bonding system.2:39 To prevent galvanic corrosion, install a galvanic isolator or an isolation transformer.4:50 Alternatively, disconnect shore power when not actively charging batteries, relying on solar power or other independent sources to maintain the battery bank.4:58

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