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hmalaga's avatar
hmalaga
Explorer
Dec 03, 2019

Solar power battery novice question

I recently purchased a Used Fox mountain by Northwood that has solar power using Go Power equipment. The control panel allows you check battery status by pushing a series of buttons to scroll thru it’s status. The panel directions say that it can be wired to show status of two individual batteries. My panel does not show status of the second battery. Trailer has two interstate 12 volt batteries wired in parallel. The panel says battery is at 100%. I have checked both batteries with my multimeter and they are both charged. So I figured I should check the control panel to see if the option for second battery readout was wired for the second battery. I have not done that because I started wondering if the fact that the two batteries were wired in parallel was simply allowing the solar to charged both batteries as if they were one and thus the read out at 100% was a reflection of the two? I am not an electrical guy and am limited in my knowledge of solar in general. So is my thinking totally missing the mark with my parallel charging theory or not? Thank you for any guidance or insight you can provide.
  • Your thinking is correct.
    The two 12v batteries wired in parallel act as one battery and are both being charged via the solar panels. The readout is displaying the voltage of the two batteries is if it were one battery.
  • This might be what you have: (scroll down to "dual bank")

    https://gpelectric.com/product-category/solar/page/2/

    Lots to read on how the controller works in the "Products" links.

    If you believe that battery SOC from a solar controller, you are living in fantasy land. You need an hydrometer to check the SG for the real SOC. Also your own battery voltage reading does not give you the SOC unless the batts have been disconnected entirely for an hour or so (actually a day is more accurate, but an hour gives you a "close enough").

    The controller does not know where its output amps are going. How much to loads and how much to battery. (Not talking about the "load" terminals--just the "battery" terminals which also have loads as well as battery) An actual battery monitor such as a Trimetric shows battery only. Even it needs to be calibrated (reset) fairly often using the SG with Flooded batts or its ammeter with AGMs.)

    In their blurb they say the batts are at 100% when they reach the high voltage set-point. That is false. That is just the start of the Absorption Stage.

    Anyway, you will figure it all out best by watching it work while camping. Just don't believe that SOC reading!
  • Two batteries refers to 2 different banks common in MHs with chassis and house batteries, each bank can have multiple batteries. Your 2 batteries wired in parallel is one battery.
  • Thank you for the responses. It’s great to know I’m on the right track with much still to learn.

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