Comments: Sunny Buddy Solar Charger V13 Hookup Guide


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  • Member #1507015 / about 5 years ago / 1

    It seems like the resistor network it set for 4.0 volt float charge and not 4.2 which is usual for LiPo. Is that correct?

  • Member #1486138 / about 6 years ago / 1


    I've connected solar panel and battery (3.7 LiPo) to my Sunny Buddy. I've got onlu 0.14V on load side and cannot power my devices. Battery is fully charged. Any clue what may be wrong ? Anyone ?

  • Member #1482916 / about 6 years ago * / 1

    Hello there,

    It looks like a solar panel comes with a male connector to connect the MPPT solar charger, how can I get an MPPT solar charger sample? Can you make it much smaller? we would love to consider it to an integral solar panel charger?

  • Angel Z / about 6 years ago / 1

    Hello, I got a little confused with the r_sen resistor. Should it be connected in parallel with the R1? What resistor value do i need to add to get an 2A charging current?

  • Trevor_J_S / about 6 years ago / 1

    Could this be used to charge from small a water turbine generator such as this:

    If not, any suggestions on what I could use?

    • CF / about 6 years ago / 1

      Theoretically yes, but the Sunny Buddy is really setup for use with a solar panel over use with a turbine. For a water turbine like your example, a DC to DC converter along with a lipo charger would be better suited to this task.

      We only carry one DC to DC converter at the moment (BOB-09370) configured for 5 volt and that coupled with a charger like PRT-10217 would do the trick but the Sunny Buddy is less expensive than those combined.

      As long as your turbine can output output more than 6 volts continuously, the Sunny Buddy should work but might not be ideal.

  • B_Frie / about 6 years ago / 1

    If I hook up two solar panels, will the potentiometer Input Current Limit still need to be set to 3v? Thanks for your help.

  • sdcharle / about 6 years ago * / 1

    This tutorial references a potentiometer, however I don't see one on the board (or in the photos) and it's V13. Am I missing it somehow?

    (edited to add)

    Found it, white rectangularish thing in lower left corner - hadn't seen one like this.

  • ciakki_g / about 8 years ago / 1

    Will the Sunny Buddy take energy from the battery to give it to the load, for instance in a cloudy day or at night? Thanks

  • MCsolar / about 8 years ago / 1

    I want to make a solar charger with your sunny buddy but i want to add network topology and add some ports, mi charger have 3 panels with a battery of 6000mah :) please reply the most possible you can.

  • MCsolar / about 8 years ago * / 1

    Hi your Sunny Buddy is great and actually im gonna make a solar charger but i need to change adding switches, lights and ports on the sunny buddy, im going to put in my charger 3 panels and a li-po battery of 6000mah, can i do that? its possible change ports and add other specifications to the sunny buddy? Please reply the most possible you can.

  • Daniel S / about 8 years ago / 1

    Is there any documentation for what the Fault light actually represents? I think my Sunny Buddy is faulty, and I am measuring a voltage on the Fault pad (referenced to ground) but don't know what this means.

  • Member #456729 / about 9 years ago / 1

    Hi, is it possible to use two of them with load connected in series to have a 7,4 power supply?

    • SFUptownMaker / about 9 years ago / 2

      Yes. They are, in fact, designed to be connected in this way.

  • Olivier.V / about 9 years ago / 1

    Hi, nice stuff. Do you think I can charge Supercap with this solar MPPT charger? I've not found any indication in the LT datasheet. Thank you. Olivier

    • SFUptownMaker / about 9 years ago / 2

      Probably. It'll servo the charge current based on the LiPo profile, though, so it likely won't be as efficient as a dedicated super cap charge circuit.

  • How do I know when the battery is finished charging? There are no indicator lights? Is the idea (not spelled out anywhere?) to put LEDs in the Charge, Fault, Set, Gnd holes?

    • SFUptownMaker / about 9 years ago / 2

      You could do that; those signals are open drain so if you connect an LED anode to the supply and cathode (with resistor) to the Charge hole, you'll get an indicator.

      There aren't any on the board to avoid any kind of constant current drain that's not absolutely necessary.

  • Member #1667542 / about 3 years ago / 0


    my sunny buddy is connected to a 30 W solar panel, and on load side an ACS712 5A which is now measuring 3.93V and 7.75 A. Do you think it is getting the correct measurements I'm a bit confused.

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