Victron Energy Galvanic insulator VDI-32

Galvanic insulator VDI-16, VDI-32 and VDI-64

The galvanic isolator prevents electrolytic corrosion. It blocks low-voltage direct currents,
that enter your boat via the shore power ground cable. These currents can cause corrosion to the metal parts of the boat underwater, such as the hull.
of the boat underwater such as the hull, propeller, shaft, and so on.
The galvanic isolator consists internally of two diodes connected in an anti-parallel manner.
By connecting them in this way, the diodes allow the current to flow in both directions,
but only when a certain voltage threshold is exceeded. The voltage,
at which the diodes conduct is 1.4V DC.

The isolator is installed directly behind the 230 V connection of your boat. The forward voltage of the
galvanic insulator is higher than the potential difference between metals. This means that the
voltage does not allow conduction and the galvanic isolator thus prevents any electrolytic current.
However, if a (higher) fault current occurs in the AC circuit, the diodes allow the current to pass and the
residual current device interrupts the circuit.