battery monitors in a circuit Bat 1 ,Bat 2 ,Both

[rubino]

My boat ha two batteries with a switch Bat 1 , Bat 2 ,Both. As far as I know this circuit needs Two battery monitors ... but what does happen when the switch is on Both ? Quite confused . Thank you.

[Stu Jackson]

These might help:

OEM 1-2-B Switch Wiring History Alternator/Batteries & "The Basic" 1-2-B Switch BEST Wiring Diagrams

Basic Battery Wiring Diagrams This is a very good basic primer for boat system wiring: Basic Battery Wiring Diagrams

This is another very good basic primer for boat system wiring: The 1-2-B Switch by Maine Sail (brings together a lot of what this subject is all about)
http://forums.catalina.sailboatowner...d.php?t=137615

This is a newer primer for boat system wiring design with a thorough digram: Building a Good Foundation (October 2016)
http://forums.sailboatowners.com/ind.../#post-1332240