Page 2 of 2 FirstFirst 12

Thread: Someone gave me a panel - can I build on it?

  1. #11
    Join Date
    Mar 2012
    Location
    US-based but traveling
    Posts
    124
    It is about 16" x 36". It's a unisolar 21, which comes mounted in an aluminum frame. Pretty handy.

    My fridge is mainly to keep my film from getting cooked in the sun. Cold beer is a nice ancillary benefit. The fridge will spend most of its time set at ~55f unless I am trying to chill a 6 pack or the occasional perishable. As for battery availability, I can use whatever physically fits in my battery tray, AGM or otherwise, so I'm not too worried about that.

    But still, point taken.

    I estimated 80watts would overcome my general fridge usage. I'm not opposed to adding another panel to the mix but only if I can do it on the cheap. I am overscoped and underbudgeted as it is

  2. #12
    Join Date
    Nov 2010
    Location
    Middle of Nowhere, Outer Skin of Space Ship Earth, 1 A.U. from Sol, Outskirts of Milky Way.
    Posts
    2,813
    Oh those. I forgot about those. Don't think they make them anymore.

    Yea, those aren't the stick-on Unisolars.
    ...
    ...
    Current: 76 E-250, bubble-top, self-contained|couple of old Yamaha enduros
    Previous wheelers: 41 Willys|78 FJ40|78 Bronco|84 Bronco|74 Ramcharger|78 Ramcharger|79 D150 PowerWagon|77 D100|79 D400 dually, converted to 4WD, utility bed, 10' Lance|75 Westy|69 Scout, RHD|bunch of others|bunch of bikes|couple of boats|couple of motorhomes|blah blah|so what|not my idea|just doin' what I'm told|wank wank|this space for rent|candy is dandy|but liquor is quicker

  3. #13
    Join Date
    Mar 2012
    Location
    US-based but traveling
    Posts
    124
    I'm thinking about putting one of these up there. $80 for some piece of mind and battery longevity seems like a good idea.

    http://www.solarblvd.com/Solar-Panel...duct_info.html

    I have to figure out how I'll mount it to my roof rack and how I'll pass the wiring into the vehicle before I proceed.

  4. #14
    Join Date
    Mar 2012
    Location
    US-based but traveling
    Posts
    124
    Orientation - on my roof I could install the panel flat on top of my roof rack, removing some of the rack's utility.

    Alternatively, I could mount it in front of the rack in which case it would be angled forward slightly - the rear would be ~6" higher than the front.

    For a mobile automotive install, I doubt this will make a big difference right? I imagine I'll get better results from the angled install when I park into the sun and worse results when I don't.

  5. #15
    Join Date
    Mar 2012
    Location
    US-based but traveling
    Posts
    124
    Ok guys - I bought a morningstar sunsaver ss-10 and an 80 watt panel. I wired my existing Unisolar panel in parallel with the one from solarblvd and connected that to the solar leads on the sunsaver.

    The green LED light comes on to say it is charging but I don't get any output if I put a voltmeter or ammeter on the battery or load leads from the controller. Is that odd? I was expecting to see something on the meter. Does this controller only work if connected to a battery?

    Should I be fusing cable between the panels & the charge controller or just between the controller & the battery? I'm thinking about a short that might occur where I pass the wiring from the roof of the vehicle into the cabin. I doubt the panels could produce enough current to melt anything but should I be doing anything to protect the panels themselves?

  6. #16
    Join Date
    Jul 2011
    Location
    Tucson AZ
    Posts
    24
    That controller is designed to charge a battery. It needs a battery on its output to do anything. Its not like a power supply that puts out voltage whether there is a load or not. If you hook up a fully charged battery you won't see much. Try putting a load on the battery, like a brake light or turn signal bulb. You should see at least 2A out of the controller with that load.

    A word of warning: Some charge controllers will be destroyed if they have power on the panel connections but no battery connected. I destroyed a 4.5A SunGuard unit that way at work a few years back. No smoke, no flames, just dead. I hope for your sake the SS-10 does not have that issue.

    Since you are going through a metal roof with your wiring a fuse at the panels would be a good idea, but not necessary. They are limited to about 6.5-7A short circuit current and even 16AWG wire can handle that without melting. You should be using at least 12AWG there. You could fuse them at 10A. AFAIK the panels can put out short circuit current all day with no damage.

  7. #17
    Join Date
    Nov 2010
    Location
    Middle of Nowhere, Outer Skin of Space Ship Earth, 1 A.U. from Sol, Outskirts of Milky Way.
    Posts
    2,813
    Voltmeter across the terminals will always show whatever voltage the battery is at. So if the battery is at 13v, then that's what you'll see everywhere. [EDIT: NOT true with an MPPT controller.] As the battery voltage rises over time, you'll see that higher voltage everywhere you put the meter across the +/- terminals. The battery limits the voltage of the whole system.

    Ammeter has to be in series to measure amp flow. As in, disconnect the solar + from the charge controller, connect the lead from the solar to one probe on the meter, and stick the other probe in the charge controller +. Make the power flow THOUGH the meter. Be careful - my multimeter is limited to 10a when used as an ammeter. Anything over that will pop an internal fuse. Also have to move the probe to a different hole in the meter to measure amps with it.

    Do it on the SOLAR side of the charge controller. I believe all Morningstar charge controllers specify hooking up the battery first. Because that's where they get their power to operate.
    Last edited by dwh; 05-15-2012 at 01:45 AM.
    ...
    ...
    Current: 76 E-250, bubble-top, self-contained|couple of old Yamaha enduros
    Previous wheelers: 41 Willys|78 FJ40|78 Bronco|84 Bronco|74 Ramcharger|78 Ramcharger|79 D150 PowerWagon|77 D100|79 D400 dually, converted to 4WD, utility bed, 10' Lance|75 Westy|69 Scout, RHD|bunch of others|bunch of bikes|couple of boats|couple of motorhomes|blah blah|so what|not my idea|just doin' what I'm told|wank wank|this space for rent|candy is dandy|but liquor is quicker

  8. #18
    Where the cables pass through the roof:

    Watertight and chafe preventative products.

    http://www.amazon.com/Arlington-LPCG...ref=pd_cp_hi_0

    I would not try to run the system without a battery attached.

  9. #19
    Join Date
    Nov 2010
    Location
    Middle of Nowhere, Outer Skin of Space Ship Earth, 1 A.U. from Sol, Outskirts of Milky Way.
    Posts
    2,813
    Quote Originally Posted by WideAngleWandering View Post
    I doubt this will make a big difference right? I imagine I'll get better results from the angled install when I park into the sun and worse results when I don't.
    More like you'll get results when you park in the sun, and no results when you don't.
    ...
    ...
    Current: 76 E-250, bubble-top, self-contained|couple of old Yamaha enduros
    Previous wheelers: 41 Willys|78 FJ40|78 Bronco|84 Bronco|74 Ramcharger|78 Ramcharger|79 D150 PowerWagon|77 D100|79 D400 dually, converted to 4WD, utility bed, 10' Lance|75 Westy|69 Scout, RHD|bunch of others|bunch of bikes|couple of boats|couple of motorhomes|blah blah|so what|not my idea|just doin' what I'm told|wank wank|this space for rent|candy is dandy|but liquor is quicker

Page 2 of 2 FirstFirst 12

Posting Permissions

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