Battery charge reading

Discussion in 'Motorhome Chat' started by greycaster, Jul 13, 2013.

  1. greycaster

    greycaster Read Only Funster

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    I have just installed a 120w solar charger on my 2001 hymer. It is connected to a ELB 99 via a LR1218 regulator. My question is how do I determine the real charge in my batteries, since hooking up the solar panel the reading on the hymer display panel shows 14v for both the vehicle and leisure batteries. I don't want to have to check at the actual batteries as they are located under the seats and I don' t want to have to disconnect the solar panel every time I want a reading.
     
  2. adds666

    adds666 Read Only Funster

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    Hi Greycaster,

    Electrically I think you will need to disconnect the solar panel momentarily while you read the battery condition display. Could be as simple as a little push to break switch that is capable of 10A.

    This is because the panel is pumping out 14v to your battery and your condition gauge is reading this.

    Either that or wait till its dark? Then the panel won't be supplying power and you can read just the battery.

    Hope this helps

    Adam
     
  3. pappajohn

    pappajohn Funster Life Member

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    as already said, you need to disconnect any charging source somehow....solar or mains

    Checking at the battery will show exactly the same voltage as checking anywhere else in the system if the solar is charging

    Wait until the sun has fully set, or better still, when its dark....that will give a more accurate reading..
     
  4. MicknPat

    MicknPat Funster

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    You could install a NASA BM1 monitor or similar that shows you not only what is going into your batteries but also what is coming out.

    [​IMG]
     
  5. pappajohn

    pappajohn Funster Life Member

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    but it will still show the solar charge voltage and not the battery voltage....unless the solar is disconnected or at night.
     
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  6. MicknPat

    MicknPat Funster

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    We have a Morningstar PS-30 controller for our 3x125 w solar panels, this as you can see has a small LED display that continually scrolls through the battery volts, solar amps and load amps :thumb:

    [​IMG]

    I also have bought a Nasa BM-1 (yet to be fitted) to tell be what is being drawn from my batteries.:Smile:
     
    Last edited: Jul 13, 2013
  7. jonandshell

    jonandshell Funster

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    The only way is the old fashioned way!:BigGrin:

    Buy a battery hydrometer!:thumb:
     
  8. greycaster

    greycaster Read Only Funster

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    Thanks for the replies, looks like the best way is to check at night. Would the reading be affected by a street lamp?
    Regards
    Greycaster
     
  9. callumwa

    callumwa Read Only Funster

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    If it is night time, the street lamp should not be an issue as the solar panel should be tucked up out of sight asleep underneath it's duvet.....:Wink:

    If you are worried about the street light or moonlight, just put a tarpaulin or something over the panel....


    :BigGrin:
     
  10. Wildman

    Wildman Read Only Funster

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    don't forget that a false "surface" surface charge remains on the batteries up to one hour after charge has been removed so give that time to settle if you want the real reading. or as has been said use a hydrometer
     
  11. pappajohn

    pappajohn Funster Life Member

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    shouldn't make any difference....unless the council fitted UV/infrared lamps :Laughing:
     
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