Forum Discussion

rightlaneonly's avatar
rightlaneonly
Explorer
Apr 28, 2014

Controller

I have a small solar panel that is putting out 18 volts in the shade, don't know the wattage. I want to use it to charge a 12 DC battery on an Aliner. Has two small LED lights inside, a propane detector and water pump. The only constant use is the detector. Recently camped for three nights and the battery dropped from 12.9 volts to 12.8 volts. That shows how little we draw on the battery. My question is this, I need a controller and don't see the need to spend a ton of money on one. I know this is not very scientific info but I'm not electric literate:?. I've found a 30 watt charger controller that say's its for a solar street light. Would this work. Any suggestions for a controller under $50.00? Thanks for any answers in advance. Oh yeah, be kind, like I said I'm pretty dumb about electrical stuff:o

6 Replies

  • rightlaneonly's avatar
    rightlaneonly
    Explorer
    Apr 29, 2014
    2oldman wrote:
    rightlaneonly wrote:
    camped for three nights and the battery dropped from 12.9 volts to 12.8 volts. That shows how little we draw on the battery.
    You don't need to spend any money. With that litte use, you don't need solar.

    True but we often camp for a couple weeks at a time, need to recharge the batt sometime, solar would do it automatically. Thanks for all the help guys. I think I'll get a controller from Amazon. I really appreciate the input.
  • time2roll's avatar
    time2roll
    Nomad
    Apr 28, 2014
    What does the panel measure? I am thinking it is just 15w or less. Just connect while in use, no controller needed.
  • westend's avatar
    westend
    Explorer
    Apr 28, 2014
    Another solution might be to install a diode on the panel wiring. A bigger spud diode would drop the voltage to a reasonable level from 18V.

    If it was me, I'd buy one of the budget controllers off of E Bay or one of the resellers that puts them on sale. A controller will make your charging system nearly maintenance free.
  • Tango__AE7UI's avatar
    Tango__AE7UI
    Explorer
    Apr 28, 2014
    Rightlaneonly,
    You already have the solar and are keeping the batteries topped off.

    If you plan on adding any additional panels I would suggest a larger controller, say 30 amps, so you won't have to change it out later.

    I went with (2) 135 watt panels and a 30 amp controller.
    I can add more panels without having to change the controller.

    It may be a little more expense up front but will handle future expansion.
  • 2oldman's avatar
    2oldman
    Explorer II
    Apr 28, 2014
    rightlaneonly wrote:
    camped for three nights and the battery dropped from 12.9 volts to 12.8 volts. That shows how little we draw on the battery.
    You don't need to spend any money. With that litte use, you don't need solar.

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