Battery condition

Discussion in 'Tech/Mech General' started by newboy, Jan 25, 2014.

  1. newboy

    newboy Funster

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    Hi
    I've had my motorhome for 3 years and always been able to use a hook-up when not in use. Unfortunately I do not have hook-up at my new storage.

    My question is I have 2 x 90amp/hr leisure batteries and I am using 0.25 volts per week.(started 13 volts, 3 weeks later 12.25volts), can anybody tell me:

    A.How many watts I am using per hr/week ?
    B.How long the batteries will last before needing charging ?

    Reason for question. Thinking of fitting a 100watt solar panel.

    Thanks in anticipation
     
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  2. pappajohn

    pappajohn Funster Life Member

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    at 12.25v your batteries are almost technically flat.

    Difficult working out a wattage from a voltage but working on 12.7v being fully charged, 12.2v being flat and combined amperage of 180 i would estimate you have used around 90 amps or approx 1000watts.

    50% discharged is considered flat

    Doesnt seem correct for a battery in storage though....are your batteries in good condition as the only thing i can think is your batteries are on their way out.

    Edit....

    Just done a quick calc and if i got it right its only 2watts or 166milliamps per hour drain or just under 4 amps per day over 3 weeks.

    Is there an LED light left on somewhere ?

     
    Last edited: Jan 25, 2014
  3. Roryboys Dad

    Roryboys Dad Read Only Funster

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    Love your batteries?


    Then they'll love a Solar Panel.


    Even this time of year – dull, cloudy, raining – the batteries will get some charge going into them.


    And in better weather …......

    :france::france::france:
     
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