Forum Discussion
opnspaces
Nov 29, 2019Navigator III
To hook up two 12 volt batteries you need to simply put the batteries side by side. Reference the picture below.
Then:
Ignore the disconnect in the picture if your trailer does not have one.

This will give you 2 twelve volt batteries wired as 12 volts.
As far as the hefty wire between the posts, I just use short battery wires with ring terminals at each end that I bought at Walmart next to the batteries. It's probably a bit overkill on wire size, but they were premade so it was easy.
- Use a wire to connect the negative posts together
- Use a second wire to connect the positive posts together.
Then:
- Connect the positive wire from the trailer to the positive post on one battery.
- Connect the negative wire from the trailer to the negative post on the second battery.
Ignore the disconnect in the picture if your trailer does not have one.

This will give you 2 twelve volt batteries wired as 12 volts.
As far as the hefty wire between the posts, I just use short battery wires with ring terminals at each end that I bought at Walmart next to the batteries. It's probably a bit overkill on wire size, but they were premade so it was easy.
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