charging a small 7amp (alarm) battery in the bush





Results 1 to 19 of 19
  1. #1
    Join Date
    Mar 2009
    Location
    Stellenbosch
    Age
    51
    Posts
    226
    Thanked: 2

    Default charging a small 7amp (alarm) battery in the bush

    Any advice on how I should charge one of those 12v 7amp "alarm batteries" in the bush? (I use the battery to power a string of LEDs)

    Can I just connect them to my 2nd battery in my car e.g. with crocodile clips or lighter plug? (I sometimes charge the 2nd battery with a solar panel and regulator if I am not driving
    )


    Name:  bat.jpg
Views: 732
Size:  7.3 KB
    Toyota Prado 4.0l Petrol
    OME Suspension
    B'rakhah Ingonyama Offroad Camper

    Previously2002 Disco TD5

  2. #2
    Join Date
    Jan 2018
    Location
    CT
    Age
    53
    Posts
    147
    Thanked: 142

    Default Re: charging a small 7amp (alarm) battery in the bush

    Don't charge directly from a car battery, or worse, a cigarette lighter socket! If you do, there would be quite a heat build-up and your 7Amp battery will not last long at all. Using your lighter socket could damage wiring. You want to be charging at a rate of only about 1 Amp for a 7 Amp battery.

    Use a small panel and charge controller if you have that available.

  3. #3
    Join Date
    Mar 2009
    Location
    Stellenbosch
    Age
    51
    Posts
    226
    Thanked: 2

    Default Re: charging a small 7amp (alarm) battery in the bush

    Quote Originally Posted by Learnercamper View Post
    Don't charge directly from a car battery, or worse, a cigarette lighter socket! If you do, there would be quite a heat build-up and your 7Amp battery will not last long at all. Using your lighter socket could damage wiring. You want to be charging at a rate of only about 1 Amp for a 7 Amp battery.

    Use a small panel and charge controller if you have that available.

    Thanks a lot! Your explanation is exactly why I posted this question! See, I tried to charge it with my 7amp C-tek and the battery nearly exploded!
    Toyota Prado 4.0l Petrol
    OME Suspension
    B'rakhah Ingonyama Offroad Camper

    Previously2002 Disco TD5

  4. #4
    Join Date
    Jun 2013
    Location
    Alberton
    Age
    59
    Posts
    6,113
    Thanked: 2591

    Default Re: charging a small 7amp (alarm) battery in the bush

    Even the 12 v charger from 4x4 direct that you plug into a wall socket steps down the V to .5 amp.

    As an alternative, you could use a 18650 battery box with 18650 batteries and compliment this with a 12v charger that will charge off your cig lighter plug.
    Lusted for a Landy but the Pajero was sexier and bigger in the right departments, just like my Missus.

    2004 Gen 3. 3.8i petrol V6 (PAJTU)
    X Factor Bundutop trailer (designed by me)
    1998 Blister Fender Pajero 3500 24V (PAJ) (Sold)
    BMW R1200R

  5. #5
    Join Date
    Oct 2009
    Location
    Stellenbosch
    Age
    70
    Posts
    3,968
    Thanked: 519

    Default Re: charging a small 7amp (alarm) battery in the bush

    Quote Originally Posted by Learnercamper View Post
    Don't charge directly from a car battery, or worse, a cigarette lighter socket! If you do, there would be quite a heat build-up and your 7Amp battery will not last long at all. Using your lighter socket could damage wiring. You want to be charging at a rate of only about 1 Amp for a 7 Amp battery.

    Use a small panel and charge controller if you have that available.
    I beg to differ.

    I have charged my 7Ah gel battery straight off the utility battery for years without any problem. Using a cigarette socket is pretty much the same thing. What saves the battery is the fact that I use about a 2m long fairly cheap and thin twin flex cable. This this introduces enough resistance into the charging path to ensure that the charge current stays within safe limits.

    The cable is the same twin type you find on alarm circuit wiring, 1A capacity I think. The battery does not heat up at all.

    Using a 10W 12V solar panel with a charge controller is also a good and sensible idea.
    Eggie.

    "Do not go where the path may lead, go instead where there is no path and leave a trail."
    - Ralph Waldo Emerson.

  6. #6
    Join Date
    May 2007
    Location
    Welgelegen, Cape Town
    Age
    57
    Posts
    1,935
    Thanked: 167

    Default Re: charging a small 7amp (alarm) battery in the bush

    I bought a small 12 v 3 amp charger from midas...for my 12v 7 A batt ..and then just plug that into my inverter to charge the batt if need be..I think it was about R450.

    Toyota D4D Legend 45
    Triton Clubcab 2x4 2.5 DID
    Bushlapa Vlooi 652

  7. The Following User Says Thank You to Kaptein Jack For This Useful Post:


  8. #7
    Join Date
    May 2009
    Location
    Hillcrest, Malaysia
    Age
    63
    Posts
    18,845
    Thanked: 6455

    Default Re: charging a small 7amp (alarm) battery in the bush

    The Midas PSA 8 Amp Charger has a 2 Amp mode for these batteries. And itís virtualy fail safe because the default stat up mode is 2 Amp.
    Cheers

    ZS5KAD
    3 V8's
    NA TwinTurbo SuperCharger
    A V6 and an inline 4

    The frogs are starting to notice that the water is getting warm but it is already too hot to do anything about it.....

  9. #8
    Join Date
    Dec 2014
    Location
    Somerset West
    Age
    77
    Posts
    459
    Thanked: 370

    Default Re: charging a small 7amp (alarm) battery in the bush

    I concur with my learned friend Eggie. I spent R350 on a special DC-DC charger for these batteries at Car-a-Camp, and when I got it home it turned out to be nothing but a plastic clip-on hat for the battery, incorporating a lighter plug and a pilot light. It came equipped with a charging lead consisting of a thin two-core wire with a cig plug at each end.

    It seems to work well though.

  10. #9
    Join Date
    Aug 2008
    Location
    Rangeview Krugersdorp
    Age
    70
    Posts
    6,417
    Thanked: 1199

    Default Re: charging a small 7amp (alarm) battery in the bush

    Been charging mine for years with this Midas cheapie...Click image for larger version. 

Name:	20180306_083822.jpg 
Views:	116 
Size:	79.6 KB 
ID:	479931
    There is no task too simple for some people to complicate !



    Hyundai Getz 1.6 2010

  11. #10
    Join Date
    Oct 2011
    Location
    krugersdorp
    Age
    45
    Posts
    1,372
    Thanked: 320

    Default Re: charging a small 7amp (alarm) battery in the bush

    i use 21W solar panel and controller
    to charge 3 of 7Ah batteries in parallel.

  12. #11
    Join Date
    Jan 2016
    Location
    Pinetown
    Age
    33
    Posts
    328
    Thanked: 310

    Default Re: charging a small 7amp (alarm) battery in the bush

    I use this little attachment. Came with a 220v trickle charger and a male to male 12v charger for on the go charging.

    Works wonderfully.
    Si Vis Pacem Parabellum


    2012 Hilux 2x4 D/L
    A few basic mods.

  13. #12
    Join Date
    Sep 2015
    Location
    Jhb
    Age
    47
    Posts
    103
    Thanked: 69

    Default Re: charging a small 7amp (alarm) battery in the bush

    Quote Originally Posted by Wandering_Soul View Post
    I use this little attachment. Came with a 220v trickle charger and a male to male 12v charger for on the go charging.

    Works wonderfully.
    Lumeno Battery Buddy from Fox and Sons

  14. #13
    Join Date
    Sep 2009
    Location
    [REMOVED]
    Posts
    2,181
    Thanked: 249

    Default Re: charging a small 7amp (alarm) battery in the bush

    Here's an idea.
    Order this http://www.communica.co.za/Catalog/Details/P0897549834 and get a small 30Watt solar panel.

    If I remember correctly a small 30 watt panel should provide up to about 21V.
    So that's 30/21 1.4A but when adjusting the DC - DC converter to 13.5V you should get 2.2A

    Cheap and dirty You have to monitor the charge level manually.

  15. #14
    Join Date
    Jun 2012
    Location
    Centurion
    Age
    56
    Posts
    1,262
    Thanked: 339

    Default Re: charging a small 7amp (alarm) battery in the bush

    Lumeno Battery Buddy

    Actually the whole Lumeno setup for LED lights with this is quite nice.
    Different lights option, cable splitter, remote switch, dimmer, motion sensor light/alarm.

    Have you checked how often you actually do need to charge? In my understanding, your battery should last quite long unless you have a hectic amount of LED lights running off it.

    Also with the battery buddy, you can power out from the battery via the provided ciggie port. So nice for a USB power adapter or 12V fan from Midas, etc
    Last edited by Toccata (Roelof); 2018/03/22 at 11:11 PM.
    Make it happen!

    2018 Mobi Lodge

  16. #15
    Join Date
    Dec 2007
    Location
    nelspruit
    Age
    63
    Posts
    684
    Thanked: 78

    Default Re: charging a small 7amp (alarm) battery in the bush

    Echo has DC-DC chargers. Use mine with a solar panel also.

  17. #16
    Join Date
    Feb 2016
    Location
    Somerset West
    Age
    47
    Posts
    367
    Thanked: 124

    Default Re: charging a small 7amp (alarm) battery in the bush

    A question for the professionals please.

    Bushpower have a 30watt solar panel kit and a battery buddy.

    Can you change the crocodile clips for a cigarette charger and plug the output from the solar regulator directly into the battery buddy ?

    The car charger is already "full" of stuff that needs charging, so we are looking at a small panel to charge the 12v 7amp battery mainly for lights.

  18. #17
    Join Date
    Dec 2014
    Location
    Somerset West
    Age
    77
    Posts
    459
    Thanked: 370

    Default Re: charging a small 7amp (alarm) battery in the bush

    I am very happy with my LUMENO charger setup, which, as has been said above is actually just a cigarette lighter port mounted on the 7 Ah battery in a convenient package. In my case, the small battery is purely for running a fan at night. I can then fall asleep with the fan running without worrying if I am putting the main aux battery, and the fridge, at risk.

    My related question though is, can I use this battery to charge my Ryobi 12V drill? The output voltage on the Ryobi mains charger seems to match, but has anyone actually tried this?

  19. #18
    Join Date
    Feb 2016
    Location
    Somerset West
    Age
    47
    Posts
    367
    Thanked: 124

    Default Re: charging a small 7amp (alarm) battery in the bush

    RodS how is your new camper van ?

    When can we pop round to come have a look see ?

  20. #19
    Join Date
    Dec 2014
    Location
    Somerset West
    Age
    77
    Posts
    459
    Thanked: 370

    Default Re: charging a small 7amp (alarm) battery in the bush

    Quote Originally Posted by Slowones View Post
    RodS how is your new camper van ?

    When can we pop round to come have a look see ?
    We are very happy with our camper but, owing to the speed with which it was designed and built, there are a few detailed issues which make it necessary to ship my 12 V drill and pop riveter off to the US with it next week.

    You are welcome to come and look, I have sent you a PM with my number/

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •