Forum Discussion

nohurry's avatar
nohurry
Explorer
Nov 10, 2014

Battery tender plus hook up question

Trailer in sig has two 12 volts in parallel. I just bought a battery tender plus to hook up for the winter. May be a dumb question, but where is the best place to connect? Not really any instructions with it, and website shows arrows pointing to the wires coming from batteries. On the neg side, it shows a W1 "balance" wire. So what have any of you done? Just hook to terminals on one of the batteries, or is there a better, or should I say, more proper way? Thanks,
  • RJsfishin's avatar
    RJsfishin
    Explorer
    Nov 11, 2014
    Keep in mind that the charger needs to be connected to a positive and a negative, but not necessarily at the battery. I myself would rather connect the charger to the battery leads in the 12v distribution center. I find that charger clamps connected long term directly to the battery, have a tendency to corrode. This would be same as a converter/charger is seldom if ever connected directly to the battery,.....most always connected to the 12v distribution center.
  • nohurry's avatar
    nohurry
    Explorer
    Nov 11, 2014
    g1g wrote:
    Not sure what web page you are looking but the one I looked at just shows batteries connected positive to positive and negative to negative with the charger hooked to one of the batteries. I don't see anything that says w 1 balance wire.
    I have mine charging 3 batteries and have them just hooked to the battery black lead on negative and red lead on positive I also have a 12 gauge wire running up to my vehicle battery to keep it charged. it is hooked the same way


    batterytender.com You click on "technical info", then "connecting chargers". It's figure 9. It says the purpose of this wire is to balance the voltage drop between the two batteries.

    Thanks for the quick responses, I think I got it. :)
  • g1g's avatar
    g1g
    Explorer
    Nov 11, 2014
    Not sure what web page you are looking but the one I looked at just shows batteries connected positive to positive and negative to negative with the charger hooked to one of the batteries. I don't see anything that says w 1 balance wire.
    I have mine charging 3 batteries and have them just hooked to the battery black lead on negative and red lead on positive I also have a 12 gauge wire running up to my vehicle battery to keep it charged. it is hooked the same way
  • Lynnmor's avatar
    Lynnmor
    Explorer
    Nov 11, 2014
    One battery hookup would be fine, but the very best way is the negative on one and the positive on the other. This will compensate for the tiny amount of resistance between the batteries.

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