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  1. #1
    RC Qualifier
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    A few questions about the ESC, motor and LiPo...

    I have a few questions, so I will number them.

    Question 1.
    If you have a 500W motor (as an example) and you use a 2S 5000mAh 25C LiPo.
    This LiPo will give 5A x 25C x 7,4V = 925W
    What will happen now? Will the ESC top the power off to 500W?

    Question 2.
    How do you determine what ESC is best to use?

    Question 3.
    If a motor can have 500W (same example) and the manufacture says that you can use a 3S LiPo with a 60A or 80A ESC... Does that mean that the ESC sends 60A x 11,1V = 666A to the motor?
    Will the power be too high then or am I missing something here?
    Last edited by Velineon; 02-07-2014 at 10:30 AM.
    E-Revo Brushless Edition

  2. #2
    RC Racer
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    Thats not the way you calculate current. The Lipo will give you 5Ax25C=125A.

    And amps x volt = ohm
    Erbe
    Bandit VXL

  3. #3
    RC Racer
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    So to your questions
    1. Battery gives 125A. Motor will never draw more than 500W/7,2V=69,4A.

    2. Look at the spec?

    3. look answer 1, but divide with 11,1V.
    Erbe
    Bandit VXL

  4. #4
    RC Qualifier
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    Quote Originally Posted by ronnyen View Post
    Thats not the way you calculate current. The Lipo will give you 5Ax25C=125A.

    And amps x volt = ohm
    Amps x volt = watt...
    E-Revo Brushless Edition

  5. #5
    RC Turnbuckle Jr. Jimmie Neutron's Avatar
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    Quote Originally Posted by Velineon View Post
    I have a few questions, so I will number them.

    Question 1.
    If you have a 500W motor (as an example) and you use a 2S 5000mAh 25C LiPo.
    This LiPo will give 5A x 25C x 7,4V = 925W
    What will happen now? Will the ESC top the power off to 500W?

    The ESC has no control over what is being drawn in amperage or wattage. The only thing it can control is the pulse width which controls the rotational speed of the motor. The motor is what draws the amperage.

    Question 2.
    How do you determine what ESC is best to use?

    By motor limitations plus 10-20% minimum. More if affordable.

    Question 3.
    If a motor can have 500W (same example) and the manufacture says that you can use a 3S LiPo with a 60A or 80A ESC... Does that mean that the ESC sends 60A x 11,1V = 666A to the motor?
    Will the power be too high then or am I missing something here?

    Answered in #1.
    Answers are in red.
    Whatever it is I just said... I could be wrong.

  6. #6
    RC Racer
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    Quote Originally Posted by Velineon View Post
    Amps x volt = watt...
    Sorry, you are absolutely right.. nothing to see here, move along
    Erbe
    Bandit VXL

  7. #7
    RC Qualifier
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    Thanks for the help guys!
    I will just move along.
    E-Revo Brushless Edition

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