SeaBis Marine System - Exclusively Prevents Electrolysis Corrosion.
LAND SeaBis System click: here

SeaBis Manual Switch to Multiple Engines or Batteries: Wiring Diagram.

Recommended for recreational vessels only.
The switch will select once source of power at a time and must be rotated to every position at least once per month. This example is for three sources of power - engines and an auxiliary generator, each with their own battery bank. Three sources of power (potential electrolysis) so 3 points to monitor. For 4 sources add a fourth switch position and a fourth pair of contacts. Click here.

Commercial vessels use one SeaBis hard wired to every non paralleled source - independent battery bank.