1. Welcome Hearth.com Guests and Visitors - Please enjoy our forums!
    Hearth.com GOLD Sponsors who help bring the site content to you:
    Hearthstone Soapstone and Cast-Iron stoves( Wood, Gas or Pellet Stoves and Inserts)
    Caluwe - Passion for Fire and Water ( Pellet and Wood Hydronic and Space Heating)

Question on my UPS

Post in 'The Green Room' started by olddawgsrule, Nov 13, 2011.

  1. woodgeek

    woodgeek Minister of Fire

    Joined:
    Jan 27, 2008
    Messages:
    2,576
    Loc:
    SE PA
    Your arrangement makes sense. I think one diode per panel will be useful if you have any shading issues at all, but cost you a few % output if you don't. Of course, it wouldn't help with a panel going open circuit, but it sounds like you have that under control.

    One thing not mentioned....a fuse near the battery, or ideally in its box. I have a little 'micro' system I set up, 20W panel and 40 Ah battery. I put a 30A automotive fuse in the box for safety. While it is low voltage, a big battery can certainly start a fire through a short.

    Helpful Sponsor Ads!





  2. Jags

    Jags Moderate Moderator Staff Member

    Joined:
    Aug 2, 2006
    Messages:
    14,766
    Loc:
    Northern IL
    Good to hear that you got them soldered back up.

    And No, I don't believe a 15W panel and an 11W panel in parallel will reduce your output from the 15W.

    Edit: I am not a solar junkie, so maybe there is something that I am unaware playing into this. I simply know zoomies.
  3. olddawgsrule

    olddawgsrule Member

    Joined:
    Jan 16, 2010
    Messages:
    155
    Loc:
    Southern NH
    I need to thank you once again for the suggestion.
    The site is as good as this one.
    Fast response from knowledgeable folks!
    I will also recommend the site if we can not find a solution here.
  4. olddawgsrule

    olddawgsrule Member

    Joined:
    Jan 16, 2010
    Messages:
    155
    Loc:
    Southern NH
    You have the fuse setup between the charge controller and the battery?
    Or between the panels and the charge controller?

    I'm setting up a control circuit (like I don't have enough projects) and believe this could be a good addition.
  5. olddawgsrule

    olddawgsrule Member

    Joined:
    Jan 16, 2010
    Messages:
    155
    Loc:
    Southern NH
    I popped over to the site Slow1 recommended and they confirmed my understanding.
    It will reduce production, but it looks like not all the way to the 11 watts.
    I'm still trying to fully understand it myself...

    Mis-match of watts or voltage leads towards the smaller of the watts/voltage.

    If I have it right (which I'm still working on/learning), I would need to setup a second array/charge control to add these 11 watt panels and gain what they produce in addition to what I have already.

    Seems like quite a pain in the butt...
    I know, go out and buy a 200 watt panel and get it over with....
    If only I could find the deal locally (no shipping involved)...
  6. Jags

    Jags Moderate Moderator Staff Member

    Joined:
    Aug 2, 2006
    Messages:
    14,766
    Loc:
    Northern IL
    Cool, so it acts like two resistors of different sizes in parallel. Your final resistance will neither be as high as the big one, but won't be as low as the small one.
  7. woodgeek

    woodgeek Minister of Fire

    Joined:
    Jan 27, 2008
    Messages:
    2,576
    Loc:
    SE PA
    I have a fuse at the battery, nearest the + terminal, such that if I shorted anything outside the battery box, either on the line to the controller or the line to my inverter, it would pop the fuse, rather than surge through the wire and start a fire. Shorting the panels is not really a hazard (esp for these small panels).

Share This Page