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cruz-in's avatar
cruz-in
Explorer
Feb 24, 2015

Wire Size to Connect 2 12V Batteries?

Hi Team,

Was helping a friend clean their battery terminals and noticed her two 12 Volt batteries were paralleled with about 12 gauge wire. Seemed small to me. The coach power/ground wires are 6 gauge.

I would appreciate your input in

1) Is this a hazard?

2) What is the proper size wire for connecting two 12 volt batteries?

Thanks
Dan

23 Replies

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  • donn0128's avatar
    donn0128
    Explorer II
    Feb 24, 2015
    Wire size is determined my amperage rating. If the battery is capable of producing XX amps then you need XXX wire gage. Typically I would go no less than 8ga wire. But ideal welding cable would be perfect
  • RJsfishin's avatar
    RJsfishin
    Explorer
    Feb 24, 2015
    The wires need to carry 1/2 the current being pulled from both batteries. It is probably ok, but why not at least 6-8 ga for the interconnect

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