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Thread: connecting panels to a MPPT controller

  1. #1
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    Smile connecting panels to a MPPT controller

    Hi, can panels of different voltages like 12v and 24v be connected together in series or parallel to a MPPT BZ controller? I was thinking of wireing 2 12v panels in series and joining that to a MPPT controller with an additional 24v panel into the controller also. Thanks, Kennb
    Last edited by Kennb; 09-08-2012 at 09:04 PM. Reason: clarification

  2. #2
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    Simple answer is It depends.

    However if the panel Voc and Vmp are roughly equal, within 1 volt, you can connect them in parallel. The voltage of the parallel panels will be limited to the lowest rated panel.

    Is the Isc and Imp are roughly equal, they can be connected in series. Th ecurrent will be limited to the lowest rated panel.
    MSEE, PE

  3. #3
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    Default lowering voltage in panels

    can a 24v 170w panel be re- wired in the junction box to change to 12v by connecting diodes or any of the output connections?

  4. #4
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    Why on earth would you ever want to do that for?
    MSEE, PE

  5. #5
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    Quote Originally Posted by Sunking View Post
    Why on earth would you ever want to do that for?
    What is a better idea because all my equipment is 12v and I've got this one 24v panel and am trying not to buy a new charge controller.By crossing 2 terminals it reduces the VOC to 21v. Can this be connected to a 12v controller (should it be MPPT)? Also "why on earth " etc, is the same for me as well as all the 24v panel manufacturers who print instructions for doing just that. If you cant give an answer then dont reply with stupid return questions.

  6. #6
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    If you have a MPPT controller depending on the type you can use a 100 volt panel to charge a 12 volt battery. Look at th econtroller specs and take a look at the max Voc rating. If it is more than your panel Voc you are set to go. Just do not go below 22 Voc for the panel. If you have a 24 volt battery panel the VOC should be around 44 volts.
    MSEE, PE

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