Yet another flat habitation battery.

Discussion in 'Motorhome Chat' started by Touchwood, Mar 6, 2016.

  1. Touchwood

    Touchwood Funster

    Joined:
    Aug 23, 2011
    Messages:
    749
    Likes Received:
    697
    Location:
    NE England
    I'm in need of advice yet again. My habitation battery is quite new (110AH Banner bought from Alpha batteries just over a year ago) so I was disappointed to say the least to find it flat when I needed to use the habitation lights on Friday night.

    First question; am I mistaken in thinking that it should hold its charge for quite a long time without use? We last used the MH in November of last year (I know, disgraceful, we've been busy!) and since then it's been stood in my yard apart from a couple of brief runs out to keep things moving - no use of the habitation battery on those occasions. I'm confident there's no drain on it (though I confess the main power switch had been left "on") and it hasn't been that cold here - we live very close to the sea and rarely get frosts.

    Second question; if it's not faulty and it's normal for it to lose charge in these circumstances, how likely is it that it's been damaged by this? I've recharged it via a hookup from the house (24 hours on charge) When taken off charge the MH voltmeter showed 13.7 v. I put all the internal lights on and this dropped to 13.1 v - after 3 hours with all lights on it had dropped to 12.3 v., recovering to 12.7 v. when I turned the lights off.

    The battery has a four year warranty so if it is faulty it shouldn't be a problem.

    Thanks in anticipation.
     
  2. MH 55 FUN

    MH 55 FUN Funster

    Joined:
    Feb 18, 2016
    Messages:
    2,000
    Likes Received:
    2,951
    Location:
    South West Wales.
    I would suggest that 13.7v is a little low for a supposed fully charged battery
     
  3. tonka

    tonka Funster Life Member

    Joined:
    Jul 2, 2008
    Messages:
    5,342
    Likes Received:
    7,604
    Location:
    Cannock, Staffs or Benidorm, spain
    Some vans have a continual drain, like newer Autotrails..
    The Sargent unit will take sometime like 0.2 amps on standby, over time that mounts up and will flatten a battery unless you have a solar panel and it is set up to charge..
     
  4. Clickem

    Clickem Funster

    Joined:
    May 20, 2014
    Messages:
    212
    Likes Received:
    142
    Location:
    Northumberland
    We have a reversing camera wired into our Hab battery which would be flat in a fortnight - leave on EHU
     
  5. Touchwood

    Touchwood Funster

    Joined:
    Aug 23, 2011
    Messages:
    749
    Likes Received:
    697
    Location:
    NE England
    I don't trust the MH voltmeter - I should really have checked it with my multimeter.
     
  6. MH 55 FUN

    MH 55 FUN Funster

    Joined:
    Feb 18, 2016
    Messages:
    2,000
    Likes Received:
    2,951
    Location:
    South West Wales.
    Agreed ! :)
     
  7. John Laidler

    John Laidler Funster

    Joined:
    Jan 9, 2013
    Messages:
    8,586
    Likes Received:
    11,574
    Location:
    Plympton, Devon
    0.2 amps over a 30 day month is 144 Ah which means a single battery will be flat in less than a month and even two leisure batteries will be struggling.

    Since November (three months) a drain of just 50 mA will flatten a typical battery.
     
    • Informative Informative x 1
  8. GJH

    GJH Funster Life Member

    Joined:
    Aug 20, 2007
    Messages:
    27,260
    Likes Received:
    34,540
    Location:
    Acklam, Teesside, originally Glossop
    I should think it is just the length of time it has been stood Mike. As others have said there is going to be a drain anyway. Over winter (when shade means reduced sunlight getting to the solar panel) I check both batteries regularly and use EHU when necessary. I used to do the same when we had the Autoquest.
     
  9. Touchwood

    Touchwood Funster

    Joined:
    Aug 23, 2011
    Messages:
    749
    Likes Received:
    697
    Location:
    NE England
    Thanks to all. I'll make sure to put it on hookup more often in future; I just hope it hasn't damaged it.
     
    • Like Like x 1
  10. Techno

    Techno Funster Life Member

    Joined:
    Jul 28, 2010
    Messages:
    13,864
    Likes Received:
    14,523
    Location:
    Leeds the one up North
    A fully charged battery is 12 .7 volts.
    13 .7 is the charger voltage and if you just switched the charger off it will take quite a while for the voltage to settle.
    It sounds fine to me

    Dropping to 12.3 over a period with the lights on and then recovering to 12.7 when switching them off would indicate a healthy battery.
     
    • Like Like x 1
    • Useful Useful x 1
  11. Touchwood

    Touchwood Funster

    Joined:
    Aug 23, 2011
    Messages:
    749
    Likes Received:
    697
    Location:
    NE England
    Phew! Thanks Andy.
     
  12. Techno

    Techno Funster Life Member

    Joined:
    Jul 28, 2010
    Messages:
    13,864
    Likes Received:
    14,523
    Location:
    Leeds the one up North
    A typical state of charge chart
    V open circuit means nothing going in or out.
    [​IMG]
     
    • Informative Informative x 4
  13. campa cola

    campa cola Funster

    Joined:
    Oct 5, 2012
    Messages:
    2,804
    Likes Received:
    5,650
    Location:
    Weegeland
    Why on earth is your camera live and for that matter wired into your hab battery :Eeek:??????
     
  14. funflair

    funflair Funster Life Member

    Joined:
    Dec 11, 2013
    Messages:
    4,512
    Likes Received:
    4,776
    Location:
    Guisborough
    Solar panels would keep it all charged if you keep it outside.

    Martin
     
  15. pappajohn

    pappajohn Funster Life Member

    Joined:
    Aug 26, 2007
    Messages:
    29,484
    Likes Received:
    16,967
    Location:
    YO11 2BD
    All batteries have a self discharge rate.
    If left for a long period, even taken off the vehicle, it will still eventually go flat.
    Even a few milliamps load over a few months will speed up the discharge.

    Even as low as 10 milliamps per hour soon adds up.

    4 months = 26.88 amps plus the self discharge may be as much again.
     
  16. ABZSteve

    ABZSteve Funster

    Joined:
    Jan 8, 2014
    Messages:
    737
    Likes Received:
    805
    Location:
    Aberdeen
    I use a trickle charger on my Autotrail because it will drain in 3 weeks if I don't keep it hooked up to the charger.
     
Loading...

Share This Page