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judelaurenzo25g's avatar
Jan 31, 2019

50w Solar panel and charger install help

Hi All,

I'm in the process of adding a 50w solar panel and charge controller to my enclosed utility trailer. I currently have a 10amp smart charger to keep my 35ah batter topped off. My question is, when I install my solar panel will there be a conflict between the smart charger and the panel if I'm plugged to shore power and the panel is charging my battery at the same time? I the obvious answer to me is yes... If yes, what do I need to add to my system so this doesn't happen.

Thanks,
JL
  • You question got a lot of answers with the word, Should, in it.

    Should does not cut it. Anyone know for sure?

    In theory, if the plugged-in charger just puts out a blind voltage then nothing will alter that, it will put out the voltage as long as it is plugged in.
    The solar controller (unless u got a super cheap-o one) should be sensing the charge level on the batteries and adjust the type of charging it is doing according to the voltage. Low voltage means an aggressive charge, high means a float charge.
    The plugged-in charger will fool the solar controller to think there is 14 volts (or whatever the charger puts out). A good battery will be closer to 13.6 volts or so, so less than the charger. The solar controller will always see a fully charged battery, so will likely be doing nothing except preventing solar voltage from charging. - Not a big deal since there is 14 volts charging happening from the plugged-in one.
    So, I theorize they do not work together, rather one cancels out the other.
    If you got a cheap-o solar controller then maybe it put its voltage to the battery and the plugged-in one puts its voltage to the battery and the only one that maters is whichever one is giving more voltage.
    Now, if they are both smart chargers then we need a new theory.
  • Boon Docker wrote:
    As Ivylog says there should not be a problem. They will both add to the charging.


    Great!
  • Yes, they should work together fine. Fifty watts seems hardly worth the effort.
  • As Ivylog says there should not be a problem. They will both add to the charging.

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