One last solar panel question.....

Discussion in 'Mech Tech' started by AndyC, Feb 9, 2017.

  1. Right, this is it, I'm gonna do it!

    I'm gonna fit a solar panel this spring!

    I'm decided on the panel and how I'm goind to fix it, but I don't understand the different current ratings on the MPPT controller.

    Why would I need a 20a one over a 10a one?

    Looking at the Epever Tracer 10a or 20a.
     
  2. theBusmonkey

    theBusmonkey Sponsor


    It's all about controlling output.
    So 100w panel/12v = theoretical 8 amps to deal with so you get yourself a controller that can handle this i.e. a 10 amp jobbie

    However 100w may not be enough. It's OK but I'd have more...:D

    So, 150w/12v= theoretical 12.5 amps output so you need the next controller up. A 15 amp or 20 amp.

    Future proof your system & go for a 20A one Andy. So long as cost isn't prohibitive. Ours was about £80...
     
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  3. theBusmonkey

    theBusmonkey Sponsor

    The way I figured it was that a controller that can handle higher panel outputs would also be designed to dump any excess energy (which is in the form of heat) without too much drama. Anything 'lectrical that runs cooler has to be a bonus....:thumbsup:
     
  4. OK, great.

    That makes sense.

    I was going go for 100w, but then I saw 120w, then I saw 140w. Before you know it, you've spent double the amount! :lol:
     
    theBusmonkey likes this.
  5. theBusmonkey

    theBusmonkey Sponsor

    Ay @AndyC , & the controllers are cheap relative to changing/adding panels ;)
     
  6. Oh, now I can't make my mind up between solid or flexible panel! Aghhhhh!!! :mad:
     
    theBusmonkey likes this.
  7. Following with mucho interest. I'm thinking flexible as I'd imagine the westy roof must flex considerably on the move and when lifted/dropped. Also there's quite a curve to them.
    The flexy ones seem to have a lower profile too, but that might just be my perception


    Sent from my iPhone using Tapatalk
     
  8. Pros for flexi are that they are lighter on the westy roof. Bend to match the roof curve. And don't add too much height to the bus.

    Pros for rigid Ines are that they are cheaper and appear to "fail" less.
     
  9. theBusmonkey

    theBusmonkey Sponsor

    Both @pkrboo & @Bertiebot have successfully fitted flexible panels to their Westy roofs.
    I'm sure they'd be happy to help with pro's & con's of their systems.

    Personally I couldn't be happier with our x2 90 watt panels but my tech is now over 4 years old. More compact and lightweight panels are available now.
    All I will say is buy the best you can afford. Look for marine environment rated coatings for protection and higher efficiency (ETFE is probably the best but do your tech research if you're bothered).
    Cheaper ones work OK but panel construction can be poor quality. All depends on what you want I guess.
     
    Last edited: Feb 10, 2017
    geordieandy and Razzyh like this.
  10. I'm still very happy with mine I have to say. Solar means you don't have that inevitable run down of the battery. In summer we have camped for a week and gone home with a fully charged battery
     
  11. Even if you go for a 100W panel get a 20A controller. It will work fine costs only a tiny bit more but also means if you decide to stick a second panel on you can without changing controller. I have the Epever MPPT and am very happy with it
     
    theBusmonkey likes this.
  12. Are you planning on getting a controller that puts power into just one or to both batteries?
    I fitted a single battery one on mine and wish I'd bought the 2 battery one as it'd keep the starter battery topped up too.
     
  13. Just one, as the Durite VSR should split the load.
     
    theBusmonkey likes this.
  14. Dazza

    Dazza Eyebrow not high brow

    Apologies for jumping in on the thread...has anyone fitted a panel onto.a tin top ? I've been toying with fitting a panel but I'm not sure how I'd get any wires into the van , neatly and water tight ?
     
  15. You could drill a hole in the roof and use an IP68 cable gland like this:
    [​IMG]

    I fitted one to the roof rack on my westy then just ran the wires through the rear vents to the battery.
    [​IMG]
    If you mounted it on a rack you could run the wires down the leg to the gutter.
     
    Last edited: Feb 11, 2017
    Dazza likes this.
  16. Dazza

    Dazza Eyebrow not high brow

    I did consider running into one of the vents , i dismissed using a cts gland - i wouldn't fancy drilling the roof to be honest ...mm might just look at getting one and running down the vent, probably not the prettiest solution but then again my van isn't the prettiest anyway :)
     
    Zebedee likes this.
  17. Adding another place for water to eventually get in is the reason i didn't drill my roof.
     
  18. If the cable says it is 4mm, does that mean the overall OD is 4mm?

    Just so I know what grommets/glands to buy.
     
  19. theBusmonkey

    theBusmonkey Sponsor

  20. Got one of those.
    Seems to be the best option for the cable going through the pop-top.

    Not sure what to use on the metal roof.
    Thinking just the glands on their own, or maybe get away with a good sealing rubber grommet.
     

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