Battery master thingymajig

Discussion in 'Tech/Mech General' started by simbadog, Dec 9, 2013.

  1. simbadog

    simbadog Funster

    Joined:
    Sep 12, 2012
    Messages:
    1,276
    Likes Received:
    2,178
    Location:
    Wengen
    Need some advice please :Smile:
    On my 2002 Elddis Sunseeker the charger feeds the leisure battery only, as does my 100W solar panel. I have purchased a CAK Tanks BCM12 battery charge master to allow charge to go to the main vehicle battery as well.
    I understand that I need to connect on cable to positive of leisure battery & one to earth (those are simple), but one other to positive of vehicle battery (not so easy I think).
    Do I have to run this cable all the way to battery in engine compartment or can I pick it up elsewhere???
    Confused
    Thank you
     
  2. icantremember

    icantremember Funster

    Joined:
    Sep 2, 2010
    Messages:
    5,036
    Likes Received:
    7,076
    Location:
    Nr Watton in Norfolk
    I believe if you can find it, you can connect across your split charge relay.
     
    • Like Like x 1
  3. JockandRita

    JockandRita Funster Life Member

    Joined:
    Aug 2, 2007
    Messages:
    5,653
    Likes Received:
    6,770
    Location:
    Lincs/Cambs border
    Hi there,

    I ran mine from the leisure batteries through the bulk head, and into the engine compartment. It was quite a short cable run for me. Because my solar system wasn't linked into the Eletrobloc by the original installer, my engine battery wasn't getting the benefits of any excess solar charge.

    Apart from when the panels are covered in snow, the BCM12 does it's job. :thumb:

    Cheers,

    Jock.
     
    • Like Like x 1
  4. simbadog

    simbadog Funster

    Joined:
    Sep 12, 2012
    Messages:
    1,276
    Likes Received:
    2,178
    Location:
    Wengen
    Thanks, but I don't know where that is? :Sad:

    Thanks for that, seems the simplest in terms of connections, but my leisure batt's are at the rear of the van! Cable will have to go through wardrobe, bathroom & cab to reach starter battery :Eeek:
     
  5. JockandRita

    JockandRita Funster Life Member

    Joined:
    Aug 2, 2007
    Messages:
    5,653
    Likes Received:
    6,770
    Location:
    Lincs/Cambs border
    Could you not run a thicker cable from the battery box, through the floor and along the chassis, to the engine compartment?

    Cheers,

    Jock.
     
  6. icantremember

    icantremember Funster

    Joined:
    Sep 2, 2010
    Messages:
    5,036
    Likes Received:
    7,076
    Location:
    Nr Watton in Norfolk
    Afraid I can't help you with that but I'm sure someone on here will know
     
  7. JockandRita

    JockandRita Funster Life Member

    Joined:
    Aug 2, 2007
    Messages:
    5,653
    Likes Received:
    6,770
    Location:
    Lincs/Cambs border
    No, and I can't help either on the split charge relay location. Sorry. :Sad:

    Cheers,

    Jock.
     
  8. GJH

    GJH Funster Life Member

    Joined:
    Aug 20, 2007
    Messages:
    27,227
    Likes Received:
    34,398
    Location:
    Acklam, Teesside, originally Glossop
    When I installed a BCM12 to our 2003 Elddis Autoquest 100 I connected to both terminals of the leisure battery and then ran a cable to the engine compartment similar to the manner which Jock described.

    Our Elddis was the different layout to yours of course so simpler to do that. However, I think the battery locker is similar. Without benefit of being on site, perhaps the easiest route would be to follow Jock's suggestion, taking the cable through the floor of the battery locker and along the chassis to the engine compartment.
     
  9. simbadog

    simbadog Funster

    Joined:
    Sep 12, 2012
    Messages:
    1,276
    Likes Received:
    2,178
    Location:
    Wengen
    What size cable do I need to get to run from the thingy to the engine battery? Looks like it will run under the floor?
    Thank you

    :Confused::Confused:
     
  10. GJH

    GJH Funster Life Member

    Joined:
    Aug 20, 2007
    Messages:
    27,227
    Likes Received:
    34,398
    Location:
    Acklam, Teesside, originally Glossop
    I used 5 amp, which is the same size cable as those on the BCM. As Jock suggested, though, thicker cable wouldn't do any harm. The maximum charge rate is 4 amps so it doesn't have to be particularly heavy duty.
     
    • Like Like x 1
  11. icantremember

    icantremember Funster

    Joined:
    Sep 2, 2010
    Messages:
    5,036
    Likes Received:
    7,076
    Location:
    Nr Watton in Norfolk
    I'm sure someone will correct me if I am wrong, but if you are having to run the cable a long distance then use a heavier cable, probably 10amp, to reduce any losses.

    Please ensure the cable is protected from damage where it passes through any bodywork.
     
    Last edited: Dec 10, 2013
    • Like Like x 3
  12. DavidG58

    DavidG58 Funster

    Joined:
    Feb 24, 2013
    Messages:
    6,272
    Likes Received:
    12,100
    Location:
    Bolsover, Derbyshire
    I admire you for taking this on, but wonder if it would not be better done by somebody knowing exactly what they are doing, it does not sound like it is plug and play, may be simple for some but definitely not all

    It is reminding me of some 30 years ago being told I needed rear fog lights to drive in France, but only finding out a few days before we went. I am still not actually sure I needed them but .....

    How hard could it be, bought 2 lights drilled rear bumper, back in days when there was still metal to be drilled, fitted lights, found a live supply, not really sure what it was feeding now or even how I found it, connected up lights

    Next thing was my wiring loom completely melted from back of car right to battery, luckily (but maybe not so) it did not catch fire, so I had no insurance claim but a £300 bill to rewire (1980) and had to borrow a car to go on holiday
     
    • Like Like x 2
  13. simbadog

    simbadog Funster

    Joined:
    Sep 12, 2012
    Messages:
    1,276
    Likes Received:
    2,178
    Location:
    Wengen
    I managed to fit my solar panels on roof & wire them in :Wink:
    Just wanted confirmation of a few points, better safe than sorry!
    :Smile:
     
    • Like Like x 2
  14. DavidG58

    DavidG58 Funster

    Joined:
    Feb 24, 2013
    Messages:
    6,272
    Likes Received:
    12,100
    Location:
    Bolsover, Derbyshire
    No offence intended, you clearly are much braver than me, I don't even like going on the roof to clean it, let alone drill a hole in it!!

    I once 'borrowed' a solar panel, years ago when they were not as popular as they are now, one with a stand to put on ground and clip on to battery

    How was I to know you needed a regulator, that 'free borrow' cost me my leisure battery

    I now either do without or find someone who can do for me

    :thumb:
     
    • Like Like x 2
  15. hilldweller

    hilldweller Funster Life Member

    Joined:
    Dec 5, 2008
    Messages:
    26,415
    Likes Received:
    25,067
    Location:
    Macclesfield
    I've just fitted one.

    On a Burstner with Electroblock under the driver's seat it's dead easy, both battery cables and ground are right there with screw terminals.
     
    • Like Like x 1
  16. Kool Kroozer

    Kool Kroozer Funster

    Joined:
    Apr 19, 2014
    Messages:
    1,037
    Likes Received:
    1,686
    Location:
    Cannock Staffordshire
    I have just fitted one also - really easy to do - 3 wires, 1 to negative/ 1 to + on the engine battery and the other to + on the leisure battery... dead simples an works a treat, an worth its wieght in gold IMO:thumb:
     
  17. Tmesis

    Tmesis Read Only Funster

    Joined:
    Mar 28, 2013
    Messages:
    29
    Likes Received:
    10
    Location:
    Surrey
    What does the unit achieve in the real world? The starter battery is going to go flat only when the vehicle is being laid up unless there has been laxness in fitting habitation accessories to the starter battery. So why not just have a switch to common the hab batteries to the starter battery when laying the vehicle up so that the solar keeps them both going?

    What am I missing here?
     
  18. TheBig1

    TheBig1 Funster Life Member

    Joined:
    Nov 27, 2011
    Messages:
    7,199
    Likes Received:
    9,581
    Location:
    Dorset
    a switch will do exactly the same, however if you forget to switch off and crank the engine it can try and draw excess current from the leisure battery

    with the bcm12 or the battery master, the charge being applied to the leisure battery from charger or solar panels is shared. both sense when the leisure battery is at full charge and divert any spare charging current to the engine battery. pretty much fit and forget, unlike a switch
     
    • Like Like x 2
  19. Kool Kroozer

    Kool Kroozer Funster

    Joined:
    Apr 19, 2014
    Messages:
    1,037
    Likes Received:
    1,686
    Location:
    Cannock Staffordshire
    We have a solar panel on the roof that keep the leisure battery always at max, so as soon as the engine battery drops below a certain point the leisure battery tops it back up - then the solar panel does the rest :thumb:
    PS: The only drawback i can think of with my set up is how would i ever know that the engine battery is knackered ?
     
  20. TheBig1

    TheBig1 Funster Life Member

    Joined:
    Nov 27, 2011
    Messages:
    7,199
    Likes Received:
    9,581
    Location:
    Dorset
    if either battery fails, it wont take a charge or hold charge for use the same as it would without a top up relay fitted.
     
Loading...

Share This Page