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brulaz's avatar
brulaz
Explorer
Apr 27, 2016

Balanced Battery Wiring

The general rule is that when wiring two 12V battery banks in parallel, you take the pos lead off one bank and the neg off the other.

But what if the battery interconnect cabling is much heavier (and shorter) than external leads?
Does it matter as much then?

In particular, my parallel 12V banks are interconnected with 8-12" of #1 cable, and I want to attach a #10-12 lead from my electric jack. One bank already has a neg lead to frame. I'm thinking that in this case it doesn't really matter which bank I connect the pos lead from the jack to.

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  • grizzzman's avatar
    grizzzman
    Explorer
    Apr 27, 2016
    brulaz wrote:
    The general rule is that when wiring two 12V battery banks in parallel, you take the pos lead off one bank and the neg off the other.

    But what if the battery interconnect cabling is much heavier (and shorter) than external leads?
    Does it matter as much then?

    In particular, my parallel 12V banks are interconnected with 8-12" of #1 cable, and I want to attach a #10-12 lead from my electric jack. One bank already has a neg lead to frame. I'm thinking that in this case it doesn't really matter which bank I connect the pos lead from the jack to.


    The fact is if you hook up unbalanced, you will have a battery lower then the other instead of matched. That is never good for parallel banks. That being said I see unbalanced banks.(and the early failures of the "picked on" battery) but who knows perhaps you will get lucky:)

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