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  1. #1
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    load for solar charge controller

    Hello everyone!

    im new here and also beginner for hardware design.
    I want to take the results for my mppt solar charge controller. If i do not want a battery as my load therefore what load can i use?
    This is because my objective is to determine the mppt only and the charging battery is not included in controller. So what should i connect after the DC-DC converter (boost). my output power will be 75W, and my Voc is 21V and Isc of my solar panel is 4.5A.

    Thank you!!

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    Re: load for solar charge controller

    You can try various resistor values.

    If your panel is rated 12V nominal, then a 3 ohm load will draw 4A. The resistor will need to dissipate 48W (rough estimate).

    Results are unpredictable since the mppt may boost voltage in an effort to maximize current.

    So if your load is 10 ohms, it may try to boost the output voltage to 40V or so. Its operating limits may or may not permit this.

    You may need a smoothing capacitor. Try 1000 uF for a start.



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  3. #3
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    Re: load for solar charge controller

    Search for "Electronic dummy load" with which you can vary the current through the load.



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  4. #4
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    Re: load for solar charge controller

    Quote Originally Posted by syheee View Post
    Hello everyone!

    im new here and also beginner for hardware design.
    I want to take the results for my mppt solar charge controller. If i do not want a battery as my load therefore what load can i use?
    This is because my objective is to determine the mppt only and the charging battery is not included in controller. So what should i connect after the DC-DC converter (boost).
    Hi,
    It depends on the circuit you designed if your circuit automatically senses the output battery for charging (check for 12v battery presence)you have to use a battery only for testing, if there is no such sense cicuit you can use a capacitor as the load along with a parallel resistor to sink the current
    regards ani



  5. #5
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    Re: load for solar charge controller

    This is just one example from many :

    Self-Powered Dummy Load Checks Out Multiple-Output Power Supplies
    http://electronicdesign.com/article/...ultiple-output




    Of course circuits can be adjusted to your current needs.



    http://www.gammon.com.au/forum/?id=11525

    “Let the future tell the truth, and evaluate each one according to his work and accomplishments. The present is theirs; the future, for which I have really worked, is mine.” Nikola Tesla



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