Leisure batteries connected in parallel

Discussion in 'Motorhome Chat' started by manda3000gt, Mar 31, 2011.

  1. manda3000gt

    manda3000gt Funster

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    Hi
    After replacing the 3 leisure batteries for 4 new ones I have a query as to were the cable from the charger connects and the cable to the invertor comes off, before the charger cable was connected to the no1 battery and invertor cable came off no2 so I put the 4 new ones in the same way so now have 2 batteries after the invertor cable on no2, does this matter, does the current flow one way so I would be better with the invertor cable coming off no4 and the charger cable into no1 ?
    I guess it may not matter 4x125ah and I only ran the genny for 2hrs at Newark Friday 5pm to Monday morning although they were pretty done then not enough left to start genny
    Thanks
    Dave & Amanda
    Jax & Luna
     
  2. scotjimland

    scotjimland Funster Life Member

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    It's not critical but best practice is to connect both charger and inverter on the same terminals on the first and last battery in the bank .. this will ensure that the charge and discharge current is as equal as possible in each battery.

    excuse my rough sketch
     

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    Last edited: Mar 31, 2011
  3. Jim

    Jim Ringleader

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    Excellent post jim:thumb: when discussing something like this a picture really is worth 1000 words:thumb:
     
  4. spannermanwigan

    spannermanwigan Read Only Funster

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  5. Gromett

    Gromett Funster

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    Excellent explanation :)
     
  6. scotjimland

    scotjimland Funster Life Member

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    A useful and informative site, .. but I disagree that method 3 and 4 are best practice.. and they don't take into account the OP's question about connecting the inverter ....

    'Best practice' is great in theory but must be balanced against practicality .. and the benefit gained.. if any..

    Method 2, ( the one I gave ) is the most common, considered the most practical and is used throughout industry, in fork lift trucks, golf carts, large battery banks UPS units etc. and gives a huge benefit over method 1. By comparison, the gains made from method 3 and 4 are minimal and not very practical ..

    In Method 3 when you connect the inverter you would end up with SIX (seven if you count the 12v take off for the supply to the van ) connections on two EXTERNAL POSTS how many vans have that facility ...I agree with the author's conclusion =
    In method 4 there are THREE 25 mm cables + the inverter + 12v take off on two posts .. hmm .. not easy , or compromise the system by connecting the inverter to another pair of posts thereby defeating the object.

    KISS principal ....
     
  7. spannermanwigan

    spannermanwigan Read Only Funster

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    beg to differ.

    they certainly do take all into account final five lines say it all "load and supply should always be at same connections".

    regards
    steve
     
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