Anyone know if Fuel Gauge reading is linear with resistance?

Discussion in 'Technical' started by dmhines, May 25, 2008.

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  1. Mavaholic

    Mavaholic Growing older but not up!

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    Nope. While your calculations are true, Your assuming the bi-metallic strip itself bends in in a linear motion with current. That is not true. It may take 4 times as much current for each quarter of deflection. Just to simplify the discussion and to illustrate the point, lets say it takes .1 amp to deflect it to 1/4 full. It would then take it .4 amp for 1/2 full, 1.6 amps for 3/4 full, and 6.4 amps to read full. I do not know what the actual values are, I just remember experiments from electronics school many moons ago.
     
    Last edited: May 28, 2008
    Mavaholic, May 28, 2008
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  2. dmhines

    dmhines Dixie Maverick Boy

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    Aren't the gauges 5 volts? That is what the regulator is for ...
     
    dmhines, May 28, 2008
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  3. Mavaholic

    Mavaholic Growing older but not up!

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    Yes, I was just using 12v as an example in the equations.
     
    Mavaholic, May 28, 2008
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  4. ford84stepside

    ford84stepside Lone Wolf

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    I'm glad somebody understands all that!:D
     
    ford84stepside, May 30, 2008
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  5. mavdog71

    mavdog71 Member

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    :huh:
     
    mavdog71, May 30, 2008
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  6. PaulS

    PaulS Member extrordiare

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    OK,
    Run the tank dry. Then fill it to 1/4 on the gage - how much fuel in gallons?
    fill the tank to 1/2 - how mant more gallons?
    fill the tank to 3/4 - how many more gallons?
    fill the tank to the full mark - how many more gallons.

    You will find that the gauge does not work in a linear fashon.
     
    PaulS, May 30, 2008
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