From the "that can't possibly pass building code" file

System
System Posts: 2,511 admin
in General Solar Power Topics #1
20965_257826_tl.gif

http://www.filehigh.com/viewimg.php?f=26494&i=257826

that's a in-progress pic of one of the PV strings. pictured are (2) SiemAns SR-90s (spelling wrong to avoid UBB word filter modification), and a Sharp-165.

String (2) is (3) Sharp-185s. Everything is 24v nominal except the two SiemAns panels which are in series to make 24v.

Those are simpson footings into a rafter, urethaned, each has a "through" bolt which functions as a seasonal pivot, and the panels are oriented true south. The bottom (in this picture) is the pivot. Yes the frame is just resting on top in the pic, it's secured with bolts now. Not shown is the mechanism at the top for angling the panels which is truly simple: another simpson tie-footing and I have (2) different lengths of lumber. Summer I don't use any and I just secure the pressure-treated lumber frame to the (3) PTL 2"x4" on the roof with bolts. The "fall/spring" adjuster is about a foot offset, and the "winter" one is almost 2'.

I'll take another pic later just wanted to throw up what I had and catch some laughs/flak :p

I haven't bothered to run the roof loading calculations to see what the building code would require (125# per square foot max?) but really I was focusing on using a stud finder and catching the rafters on each 2"x4" at least in one place--- a true south orientation makes that more difficult than I had thought.
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  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    #2
    Re: From the "that can't possibly pass building code" file
    JoeT wrote:
    pictured are (2) SiemAns SR-90s (spelling wrong to avoid UBB word filter modification),

    Uh. I'm now more interested in the "word filter" and what gets modified. Is there a list of bad PV words here??

    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

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  • Roderick
    Roderick Solar Expert Posts: 253 ✭✭
    #3
    Re: From the "that can't possibly pass building code" file

    That might pass mechanically, never know. Doesn't look that bad to me.

    We live in the same city, and you get to have 5 lbs per square foot, which is actually not hard to meet. You also need to have 40 lbs max per support point, and less than 18" above the roof surface. Going outside of these parameters is possible, too, but triggers the need for a review.

    And of course, there's always inspector's judgement, but if you have something sturdy, I don't see why there would be a problem.
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  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    #4
    Re: From the "that can't possibly pass building code" file

    Joe,

    A couple of observations on your array installation:

    1) Unless you live in the Tropics, the relatively small tilt angle will reduce the array's energy output, especially in the Winter. A typical year 'round tilt angle is ~ = local latitude.
    2) The lack of space behind the array will reduce natural air circulation that helps to cool the array. This too will cause an output a decrease in energy output.

    HTH,
    Jim / crewzer
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  • System2
    System2 Posts: 6,290 admin
    #5
    Re: From the "that can't possibly pass building code" file

    thks, the array is currently about 20 degrees (tough to see in pics), I made a spring/fall step and a winter step (not pictured)

    agreed there's only a 5.5" offset from the roof when mounted 'flat' like this

    , I expect underpanel temps to be BAKING in the summer.
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #6
    Re: From the "that can't possibly pass building code" file

    joe,
    i am having troubles in trying to figure what part is the bottom/top. in any case i must point out that raising the angle for winter may not have it pointing south even though it will be lower in altitude. please confirm that for yourself.
    check that no water can seep into the roof from the bolts, nails, or screws you had used in securing the wood frame to the roof. the feedthrough bolts you may have trouble with if they are standard bolts that could rust. it is better to obtain stainless steel hardware. stainless steel can 'freeze up' on you so a light oil could be used between the washers and bolt heads in addition to between the nuts and washers. also don't forget to ground your pvs.
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  • System2
    System2 Posts: 6,290 admin
    #7
    Re: From the "that can't possibly pass building code" file

    Hummmmm, first time I've ever seen PV's nailed to a 2X6. LOL
    Just kidding. Looks funny though. LOL
    Wayne
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  • System2
    System2 Posts: 6,290 admin
    #8
    Re: From the "that can't possibly pass building code" file
    crewzer wrote:
    This too will cause an output in energy output.
    he means decrease

    you probably are aware of this but just thought id mention in case. you got the right kind of joisthangers/bolts that are chemicaly compatable with the new treated lumber? something my lkuberyard pointed out to me a few yrs ago the new type of pressure ctreated lumber reacts checically with standard PT. the luber yard can give details.

    i thought this looked pretty good, if not esthetically, at least it appears solid. i presume you can not see this from the street. nice neighborhood!
    a couple small aluminum L shaped parts from PV mounting hardware kits would give youa couple inches air circulalation
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  • System2
    System2 Posts: 6,290 admin
    #9
    Re: From the "that can't possibly pass building code" file
    Wayne from NS Cana wrote:
    Hummmmm, first time I've ever seen PV's nailed to a 2X6. LOL
    Just kidding. Looks funny though. LOL
    Wayne

    lol. BOLTED, not that it matters :p
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  • System2
    System2 Posts: 6,290 admin
    #10
    Re: From the "that can't possibly pass building code" file

    Just kidding man, you should see some of the abortions I've made in the past. LOL
    But like your's, they worked and some still are working. :-D
    Wayne
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  • System2
    System2 Posts: 6,290 admin
    #11
    Re: From the "that can't possibly pass building code" file

    I'd be a tad concerned about the penetrations to the roof myself. As an ex-roofer, I know how stubborn water can be. Those pressure treated runners the pvs rest on are a perfect situation for leaves to accumulate under the panels and generate an ice dam in the winter, just like unprotected gutters can do. Just my $.02. :-D
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