Battery Voltage readouts same for both batteries?

Discussion in 'Tech/Mech General' started by Dave1966, Jan 24, 2016.

  1. Dave1966

    Dave1966 Funster

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    Hi all,

    We have recently invested in our first motorhome, an Autotrail Cheyenne which has the Sargent EC225 power control unit with a separate display unit mounted over the entry door.

    To my mind the Vehicle battery and Leisure battery readouts should be slightly different but they are *always* identical which indicates to me that there is either a problem in the Sargent or a wiring error. The van is also fitted with a solar panel and separate solar charging regulator that feeds both batteries. I can't find any information about this unit, all writing on it is in french.

    Can anyone offer any opinions based on similar experiences? Why would the Sargent solar input not be used as opposed to the 'French' unit which is an obvious addon?

    Aside from that am just recovering from a failed alternator (£450.00 fitted) and now have a leak in the roof. Back to the dealer again under warranty!

    Thanks all,
    Dave
     
  2. Lenny HB

    Lenny HB Funster

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    If both batteries are of the same type and age and charged by the same source I would expect the batteries to be at the same voltage. You could check if the panel is reading each battery correctly by checking the batteries with a multimeter, also with eHU disconnected and no solar input i.e. when it's dark , turn some lights on in the van and other items like TV, the leisure battery voltage should drop and there shouldn't be any change in the engine battery voltage.
    I don't know much about Sargent unit except the max solar they can handle is 120 watts, if you hve larger panels probably the reason for the additional regulator.
     
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  3. pappajohn

    pappajohn Funster Life Member

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    What you are seeing will be the solar input voltage which will be identical at both batteries as the controller feeds both.
    Try again an hour or so after dark and without hook up connected.
     
  4. andy63

    andy63 Funster

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    That would explain the identical voltages.... how are your voltages displayed... ie a led ladder or an actual figure... will depend on what control panel is fitted..

    I don't think the ec225 has any solar charge controler built in so it would require a separate controler regardless of panel size..
    Ta andy.
     
  5. Dave1966

    Dave1966 Funster

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    Thanks Andy, Pappajohn and Lenny.
    I'm away from the van at the moment but will check again later this week.
    Pretty sure it's the same under any circumstances though..... think I checked it while wild camping on Dartmoor at night but a bit hard to remember.
     
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  6. Dave1966

    Dave1966 Funster

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    Finally got round to checking it with no sun on panel, mains off and internal lights on to start draining the battery. Charger had been off for +/- 6 hours before the test to allow voltages to stabilise. Start voltage on both batteries identical at 12.8v, after 4 hours with all interior and awning lights on both batteries dropped to 12.5v. The readout is on an LCD panel so it's giving an actual voltage, not an LED ladder or similar.
     
  7. andy63

    andy63 Funster

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    By both batteries I'm assuming we are still talking start and leisure ..
    It does sound like there is something wrong if that's the case...The leisure lighting load shouldn't pull down the start battery voltage so unless it's just coincidence and the start battery is loaded with alarm central locking keep alive memory etc and has just settled at the same voltage at the time you checked..
    You could keep the test going a bit longer with a heavier load on the leisure side and keep an eye on voltages...
    You could also check the current draw from both batteries.. A clamp type meter would be handy...
    Just my thoughts..
    Ta andy
     
  8. Jaws

    Jaws Funster Life Member

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    As Andy has said..
    The panel shows the voltage for the leisure and cab batteries.. There is no provision on the panel to see the leisure batteries separately as ( as mentioned else where ) they are actually linked together in the loom so no point in having them shown separately :)

    I would personally say the chances of the cab and leisure batteries reading exactly the same is pretty remote to say the least, so either someone has had a fiddle to hide a fault or perhaps someone has hard wired the leisure battery(s) to the cab battery for some odd reason !
     
  9. Dave1966

    Dave1966 Funster

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    Thanks guys, time for some more investigation.
     
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