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Yosemitebobr's avatar
Yosemitebobr
Explorer
Nov 08, 2013

Installing cut-off switch for batteries

I have a trailer that has a cut off switch, however, it does not cut off everything. While in storage I want everything cut off without removing the battery cables. So, my idea is to insert a cut-off switch in the positive battery cable from the battery to the fuse. I have two 6 volt batteries in series. I want to leave the ground attached, and the jumper from battery one to battery two, opening only the positive line from the second battery. Can I do this without any detrimental effect to either battery? Leaving them hooked up that is.

7 Replies

  • beemerphile1 wrote:
    Do like you are thinking but connect the breakaway prior to the switch for safety in case it is towed with the switch open.


    Yes, I did think of that, but didn't mention it, thanks for doing so.
  • Do like you are thinking but connect the breakaway prior to the switch for safety in case it is towed with the switch open.
  • Yosemitebobr wrote:
    insert a cut-off switch in the positive battery cable from the battery to the fuse.

    Yes, you can safely do this.

    Be aware that some of the cheaper cut off switches expose a great deal of metal connected to the battery when installed. For that reason, the manufacturer recommends you install those switches on the negative side. That minimizes the risk that you will accidentally short out the battery with a dropped tool, or while working on the installation. If you prefer to use the positive side (I do prefer it there) make sure you are careful and try to add something to insulate or protect the switch from accidental shorting. More expensive cutoff switches are well designed and don't suffer from this problem as much, but may need additional cables installed from the battery to the switch mount location.
  • That will work just fine.

    However, personally, I would prefer the breakaway switch to stay connected to the battery always.

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