solar pump vfd

jakejake Registered Users Posts: 2
I want to install a remote solar pumping system using solar vfd, when I size the system I calculate that I will need 10 to 12 panels in series to get high enough voltage, this will result in more wattage then is needed, my question: Can I hook a small charge controller to the same solar panels for lights etc.


  • Dave AngeliniDave Angelini Solar Expert Posts: 6,224 ✭✭✭✭✭
    edited November 2016 #2
    This is election day here. You can do whatever you want as long as you like the limited choices!
     Seriously, you would have to know how the pump electronics would react to having a low impedence input to the CC in parrallel. Without a schematic, makes and models,
     it is dice rolling time. You could let the smoke out!
     Certainly you could manually switch between the two.
    "we go where power lines don't" Sierra Nevada mountain area
    E-mail [email protected]

  • BB.BB. Super Moderators, Administrators Posts: 32,800 admin
    In general, it is not a good idea to connect two different MPPT (including VFD) to the same solar array. Each assumes it "owns" the solar array and will attempt to figure out the optimum Vmp-array voltage. With two controllers, they will muck with the array voltage and confuse each other.

    Also, safety wise, there are few transformer isolated MPPT charge controllers (if any)--You could end up with strange ground currents and/or an electrocution potential between the two systems if interconnected to the same array.

    It is always possible it could work, but the end user usually does not have the information from the companies (schematics, programming, and such) to even know if it is a sane idea to try or not.

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • jonrjonr Solar Expert Posts: 1,386 ✭✭✭✭
    Probably easiest to find a solar pump that can use less voltage.

    I am available for custom hardware/firmware development

Sign In or Register to comment.