Originally Posted by Herk7769
The proper way to wire a pair (or more) 12 volt batteries is to use exactly the same length wires between batteries (to keep the internal resistance of that battery equal to all the others) and attach the positive of the closest battery to the charge/discharge source and the ground for the system to the negative terminal of the farthest battery from the charge/discharge source.
Herk this was the exact same info you gave me in 2012 for our Salem when i was hooking up the second battery and the marine selector switch.
it never failed us...
Do what he posted and your good to go.
if you want to incorporate a switch
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