9.87 kW Enphase installation - Roof penetration questions

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  • RegGuheertRegGuheert Solar Expert Posts: 102 ✭✭✭✭
    Re: 9.87 kW Enphase installation - Roof penetration questions
    drees wrote: »
    Any time you have a wire entering/leaving conduit, you need to use a strain relief to avoid abrasion.
    I believe that is one of the functions of the service entry head, is it not?[/QUOTE]
    drees wrote: »
    There are water proof strain reliefs which use a compression fitting which are weather proof (but it's still a good idea to keep them out of the elements as much as possible). You just need to find the right one that fits your conduit and wire(s).
    I was thinking that the service entry heads would have some sort of seal built into them, but I have not found such a thing, yet. I'll keep looking. Thanks, again!
  • mike95490mike95490 Solar Expert Posts: 8,814 ✭✭✭✭✭
    Re: 9.87 kW Enphase installation - Roof penetration questions
    RegGuheert wrote: »
    ....and my concern is that it would run down into the junction box and collect there. Did you do anything to prevent this? .....

    It's called a "Drip Loop" and since water does not usually run uphill, that's all I've ever seen.

    DripLoop2.jpg

    lotsa photos at google images
    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 ||
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  • RegGuheertRegGuheert Solar Expert Posts: 102 ✭✭✭✭
    Re: 9.87 kW Enphase installation - Roof penetration questions
    mike90045 wrote: »
    It's called a "Drip Loop" and since water does not usually run uphill, that's all I've ever seen.
    Thanks, Mike! I'm sure that will be sufficient. I guess I'm just being overly cautious. I certainly want this installation to last as long as possible!
  • dreesdrees Solar Expert Posts: 481 ✭✭✭
    Re: 9.87 kW Enphase installation - Roof penetration questions
    RegGuheert wrote: »
    I was thinking that the service entry heads would have some sort of seal built into them, but I have not found such a thing, yet. I'll keep looking. Thanks, again!
    Hmm, they don't? I haven't actually used one before, but the pics I've seen make them appear to have some sort of strain relief/seal on them - otherwise water would definitely get in during windy rain, drip loop or not.

    The pics that mr.radon posted you can see that there are small holes for the wires - you could just use UV resistant silicone sealant to plug the holes when the wires are in place, but I would have thought that there would be some sort of strain relief regardless.
  • mr.radonmr.radon Solar Expert Posts: 158 ✭✭✭✭✭
    Re: 9.87 kW Enphase installation - Roof penetration questions
    RegGuheert wrote: »
    Thanks for the details on how you did this! I've been reading about your installation for the last month or so. Excellent work!

    The service entry head that you are using looks like the ones that I picked up, only 1" instead of 3/4". I'm still not convinced that these will keep the water out. Yes, they face downward and, yes, they are under the panel. However, there can still be condensation on the wires from humid air or mist (like you get in WA often!) and my concern is that it would run down into the junction box and collect there. Did you do anything to prevent this? Are my concerns unfounded?

    No issue with condensation. Air flow for my roof even in wet weather is OUT of the head. (acts like a mini vent) The air for a roof should come in from the soffet vents and out near the top (convection flow). I felt it with my hand on one of the last warm days I was working up there.
    images?q=tbn:ANd9GcQCZWoTUAzKABpw-7KFrfBXNlHH24EWb3TfDUxvH5zm5jFJlv3PPA
    Your fears are unfounded. Its raining like the dickens right now, I have yet to notice any moisture in the attic. I go up about once a week just to check things out. (I installed 117 flashings)

    The Enphase drop down cable is routed with ties from the rails on the 6awg ground wire and I made sure to form a drip loop. Since a 6awg ground wire enters, I used it as a routing guide (zip tied to ground wire). The inspector liked this. You can bend the ground wire to form the drip loop.

    Plus this is under the panels, no rain really hits it.

    Just be sure the flashing fits the OD of the pipe, I used a 1" couple to make sure I had the right OD at the flashing penetration.

    Next time I'm up in the attic I'll snap a picture of the drop down.
  • RegGuheertRegGuheert Solar Expert Posts: 102 ✭✭✭✭
    Re: 9.87 kW Enphase installation - Roof penetration questions

    Thanks again, Mr. Radon! I appreciate the additional details. It sounds to me like your Enphase pigtails are only in the conduit long enough to get through the roof. That sounds like a much better idea than what I was thinking! I had imagined the conduit coming down into the attic and going straight into a junction box. In that case, any water which got in there would be trapped in the box. In your case, it would simply go into the attic an evaporate.
    mr.radon wrote: »
    Next time I'm up in the attic I'll snap a picture of the drop down.
    I would greatly appreciate that! Thanks!
  • dwhdwh Solar Expert Posts: 1,341 ✭✭✭
    Re: 9.87 kW Enphase installation - Roof penetration questions
    drees wrote: »
    but I would have thought that there would be some sort of strain relief regardless.

    There's no strain to relieve. If you look at the pic Mike posted, you can see that the pole drop is secured to the riser (what the pic calls the mast). Sometimes the utility requires an insulator, usually bolted to a piece of wood which is bolted to the building, or screwed directly into some wood, and stretches to that:

    http://www.fmenergy.net/images/fleming-mason/repair2.jpg

    Generally, the metal weatherheads just have a phenolic insert with a couple of different sizes of knockout holes:

    http://www.hardwarestore.com/pop-print/larger-image.aspx?prodNo=27263

    PVC has PVC knockout holes:

    http://images.orgill.com/200x200/6109672.jpg


    I don't know if a weatherhead with a seal around the wire is even sold these days. Probably, but not common. I remember seeing a very old weatherhead once that had a gasket.
  • heynow999heynow999 Solar Expert Posts: 80 ✭✭✭✭
    Re: 9.87 kW Enphase installation - Roof penetration questions

    http://www.rstcenterprises.com/soladeck/products/index.phtml
  • System2System2 Posts: 6,290 admin
    Re: 9.87 kW Enphase installation - Roof penetration questions
    stephendv wrote: »
    Looks like all the panels will be facing the same direction. At $210 per enphase (hosts pricing) and 42 of them = $8800.
    2 x Sunny Boy 5000 = $5900.

    Why would you choose enphase?

    I just picked up 10 Enphase Micros MC4 240 for
    $159 each
    $44 shipping

    Now I need to get me some racks for my roof

    Im going with the Enpase since is TO SIMPLE cheaper then heavy DC wire plan to add more
  • mr.radonmr.radon Solar Expert Posts: 158 ✭✭✭✭✭
    Re: 9.87 kW Enphase installation - Roof penetration questions

    We've had one of the wettest March's on record. For my wife I installed a UHF and VHF antenna in the attic. While I was up there I took a good look at my roof penetrations and five drop downs. I think we got 1" of rain that day. Not a drop of water coming in from the roof penetrations nor the five drop downs!
    It was blowing about 30mph while I was up there. So as far as I am concerned the drop downs work just fine.

    Mine had no rubber bushing, I used a 6AWG ground wire bent to form a drip loop with the Enphase drop down connected to it with zip ties. This creates a nice drip loop that you can easily adjust. ;)
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