Battery monitor?

Discussion in 'Campsite Electronics' started by oscrfsh, May 2, 2016.

  1. oscrfsh

    oscrfsh New Member

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    Hey guys. Im taking the pop up camper for the first time using battery power. ....I was wondering if there was anything I can get to monitor the battery so I don't let it drain down to far. I am switching to led lights inside ...mostly just charging cekll phones and tablets for the 11 year old. I was thinking of installing something like this.. http://www.amazon.com/TurnRaise-Universal-Charger-Voltmeter-Motorcycle/dp/B016O58QAK?ie=UTF8&keywords=Camper%20battery%20monitor&qid=1462237233&ref_=sr_1_6&sr=8-6
     
  2. GaJeep94YJ

    GaJeep94YJ Member

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    I've seen several posts about using this one:

    http://www.amazon.com/gp/aw/d/B00QKDXB8E/ref=pd_aw_sim_sbs_107_2?ie=UTF8&dpID=51odPNfG%2B5L&dpSrc=sims&preST=_AC_UL100_SR100%2C100_&refRID=0BZ7WC7M41XQ7E22G6YW

    Sent from my Nexus 5 using Tapatalk
     
  3. gardenbliss

    gardenbliss Well-Known Member

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    I mounted the one that Gajeep posted. It was very easy to install and it works great!
     
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  4. Customer

    Customer Well-Known Member

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    I hardwired a VOM that was free from Harbor freight with coupon.

    [​IMG]

    I have done that with the last two trailers I have owned.
     
  5. oscrfsh

    oscrfsh New Member

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    Great. I am going to look into these. How low is it safe to drain the battery ...I would like to get a solar charger..but I don't have the money at the time
     
  6. Mally

    Mally Member

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    It is recommended to not discharge below 50% of battery capacity.
     
  7. kitphantom

    kitphantom Well-Known Member Platinum Supporting Member

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    50% is the level usually recommended for standard camping batteries. We have a plug in meter to keep tabs on the batteries. There's a chart on this site: http://www.marxrv.com/12volt/12volt.htm. I printed it out and laminated it to keep it as a reference. BTW, 50% is not 6v! (It's 12.06)

    How long are you going to be dry camping? What will you be using? Anything besides LED lights and charging electronics? With our pup, we could probably go 2 or 3 days safely, but we didn't charge electronics in it. (When possible, we tend to charge the phone or iPad as we travel, and - to go with our first solar set-up - have a storage battery usually used for Kindles and phone while base camped, and a few other tasks.)
     
  8. oscrfsh

    oscrfsh New Member

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    we will be going camping for 5 nights. the lights are going to be led and only used when needed as we spend most of our night by the fire..just use the lights to change before bed. charge phones and tablets..but most of the time pones will be charged in car. maybe a laptop...but i doubt it. how will i know when the battery is half discharged...do i need to know the amps my battery holds and the gauge will read half that and thats when i know its half discharged?
     
  9. Mally

    Mally Member

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    I use a voltmeter to determine voltage. And then use this chart:
    http://dcd96xmek71bc.cloudfront.net/archives/email/Woodall's/Campground_Navigator/Navigator2011/WDN011299_12062011/Battery_Charge.jpg

    Example:
    Battery reads 12.6 or above: 100%
    Battery reads 12.42: 80%
    Etc.

    The voltage will give you the amount of charge remaining on the battery.

    There are monitors out there that will measure more than the volts. But many people, including me, just use a voltmeter to read voltage.
     
  10. oscrfsh

    oscrfsh New Member

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    the link doesnt seem to work for me
     
  11. Mally

    Mally Member

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    Sorry. Here is a chart.

    [​IMG]
     
  12. SteveP

    SteveP Well-Known Member Platinum Supporting Member

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    It helps to know the amp hours available from the battery. If it's not printed on the battery case you can probably find out from the manufacturers web site. Divide the listed value by 2 and that gives you the AH available above 50% charge. Knowing that will help you plan usage to extend your camping time.

    With the "standard" Marine/RV group 24 battery you'll have about 80 amp hours, 40 are usable.
     
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  13. oscrfsh

    oscrfsh New Member

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    i bought an everstart 29dc battery i will bhave to double check the amp hrs
     
  14. mikem12188

    mikem12188 Member

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    So this one works ok?
     
  15. tcanthonyii

    tcanthonyii Member

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    That's one of the freebies. Not a bad idea actually. I have a few floating around with bad leads.


    Sent from my iPhone using Tapatalk
     
  16. tcarlson2003

    tcarlson2003 New Member

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    Since I am also a newbie and have wondered about battery life and discharge, how do you hardwire this to the battery to be viewed in the PUP? Please and thank you!

    Well, I actually meant to attach the picture of the VOM that was hard wired, but I'm so new I couldn't figure out how to do it. Could you let me know how you hard wired it?

    Thanks!
     
  17. p

    p Active Member

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    I have a mysterious 12v battery. I charged it to 12.6 and 3 days later it went to 12.0. Now, 2 days later it is up to 12.2. The only thing on is the co2 detector.

    Does this mean I have a self charging, magical battery?

    I have not charged it during this mysterious time.
     
  18. Customer

    Customer Well-Known Member

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    The cheap/free digital VOM works fine, I have installed them in two different RVs. Cut the probes off and connect into the 12vdc wiring of the trailer. It can be wired in at any convenient spot like at a light fixture, water pump switch, 12vdc receptacle, it isn't important exactly where it is wired in providing it is always hot.

    Peter, you have a CO detector, not CO2. When you saw the lower reading there was probably a load on the battery which was not on at the higher reading. Maybe you had a light on? Nevertheless, you need to get that battery charged, it is sulfating while sitting at less than a 50% charge. Batteries must always be kept charged while in storage, unless you like buying new batteries every year.
     
  19. TRR

    TRR Active Member

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    Are you having to keep a 9v battery in the VOM?
     
  20. nizon

    nizon Member

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    thirey likes this.

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