Grundfos Solar Pump Install

Texas WellmanTexas Wellman Solar Expert Posts: 153 ✭✭
Currently working on a solar system install for a customer. This will be my 1st solar install, although not my first solar experience.

Looking for any tips or other info here.

Here's what I got so far. Water level is approximately 30-40 ft. Pump is to pump open ended into a pond. Pond level is seasonal but most water will be needed during the summer.

Wanting to do a Grundofs 11 SQF-2 or the Grundfos 18 SQF. The 11 is a helical pump, the 18 is a centrifugal pump. There will be no need for a battery backup or level controller or tank etc. It will be flowing open ended.

So far I have the pump, solar panels (2 BP 230 Watt), CU-200 controller, and of course the drop pipe and sub wire and everything else associated with installing a solar system.

I do not have the mounting bracket for the array and I don't really know where to buy one other than to have it fabbed locally. I am gathering info from my supplier. I might either install a wooden or metal pole for the base, but that's TBD. Other than small electrical supplies etc. is there anything else I'm missing?

Thanks for all your help, I'm learning as I go.


  • mike95490mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Grundfos Solar Pump Install

    You may need a backflow valve to prevent pond water (in rainy season) from contaminating the well. (and keep frogs out of the pump)
    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

    gen: ,

  • Texas WellmanTexas Wellman Solar Expert Posts: 153 ✭✭
    Re: Grundfos Solar Pump Install

    I just got off the phone with Rueben at N. Arizona and he's working me up a quote. Hopefully he'll help me clear up the fog in my head over this solar stuff.
  • WindsunWindsun Solar Expert Posts: 1,164 ✭✭
    Re: Grundfos Solar Pump Install

    Grundfos installation is pretty much like any other submersible pump, but figuring out the solar that you need can be a bit tricky.

    Although they will operate down to about 24 volts DC, it is best to keep it up higher, preferably in the 60'ish volt range for that depth to avoid excessive wire losses. You should oversize the panels about 25% based on the pump curves, more if they need longer pumping times morning and late afternoon.
  • Texas WellmanTexas Wellman Solar Expert Posts: 153 ✭✭
    Re: Grundfos Solar Pump Install

    Yeah, we sized it for 4 panels. All the mounting hardware and connectors and things are hard for a novice to figur out. I'm looking over the paperwork. Don't think my customer wants to spend that much but I'll pass it on.

    Thanks for all your help.
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