The Victron VDI-16A galvanic isolator protects boat hulls and shore power wiring from galvanic corrosion. It fits into the shore power earth conductor and blocks low-voltage DC galvanic currents while keeping full AC earth continuity intact. It is rated at 16A continuous, matching a standard single-phase shore power connection.

Key features

• Current rating, 16A continuous, suited to standard single-phase shore power connections.
• Function, blocks DC galvanic currents in the shore earth conductor without interrupting AC earth protection.
• Design, diode-based, with a blocking voltage threshold that stops corrosive currents at source.
• Weight, 1.15 kg, compact enough for confined bilge or panel spaces.
• Brand, made by Victron Energy for use with Victron shore power systems.

How it works

Galvanic corrosion happens when dissimilar metals sit in an electrolyte such as seawater or canal water, connected by a conductive path like the shore power earth cable. Small DC currents travel along that path and slowly eat away at propellers, anodes and hull fittings. The VDI-16A places a pair of blocking diodes in series with the earth conductor. These diodes have a forward voltage drop high enough to stop galvanic currents, typically below 1V, but low enough that the earth conductor still works fully for AC fault protection.

The 16A rating matches the most common shore power supply found on UK and European marina pontoons. It fits in-line on the earth conductor inside the vessel, and because it does not interrupt the protective earth under fault conditions it supports the earth continuity principle required by marine electrical standards. Check the specific standard for your vessel type and flag state before fitting.

Applications

Sailing and motor yachts on marina shore power, canal boats and narrowboats at towpath hook-ups, and any vessel where galvanic corrosion of underwater metalwork is a concern. Also used as a retrofit on vessels without existing galvanic protection.

What's in the box

• 1 x Victron Energy Galvanic Isolator VDI-16A

Installation notes

Fitting must be carried out by a qualified marine electrician familiar with the applicable marine electrical standards, such as BS EN ISO 13297 for European recreational craft. It is wired in-line on the earth conductor of the shore power inlet inside the vessel. Any wiring that bypasses or interrupts the protective earth under fault conditions creates a serious shock hazard, so confirm the installation meets the standard for your vessel type and flag state before use.