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Power supply for multiple devices -- effects on accuracy

  1. Apr 11, 2017 #1

    For my project I am plotting a Force vs Displacement graph using 2 analog inputs which are going to a DAQ.

    The two analog inputs are coming from;
    -A 5k potentiometer (for the displacement)
    -A 1000 lb load cell sensor (for the force)

    I would like to use a regulated 12V DC (1Amp) power supply for both the potentiometer and the load cell. I would like my graph to be accurate.

    I am curious as to if the output values from one device will be affected if another device is using the same power supply.

    Do I have to worry about this potential issue if I am using a "regulated" power supply?

    Here is a link to the power source I am using ;

    Here is the datasheet for the load cell;
    http://keli-cee.pl/dokumenty/134_DEFY-SS Datasheet.pdf

    Thank you.
    Last edited by a moderator: May 8, 2017
  2. jcsd
  3. Apr 11, 2017 #2


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    Do you know the specs of the supply? Do you know the accuracy requirements for your setup? If you supply an input of your DAQ as a reference that is sampling supply voltage this should improve accuracy. This will tend to cancel ripple and droop but it will not make up for errors from the sensors themselves or the DAQ.
  4. Apr 13, 2017 #3


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    In case it's not obvious... You will also need to connect the 0v of power supply to the 0v of the DAQ/microcontroller.

    You should ensure that the maximum voltage produced by the potentiometer and load cell can't exceed the max input voltage of the DAQ.

    Ideally power the DAQ/microcontroller from the same power supply as the potentiometer and load cell (via a regulator if necessary).
  5. Apr 13, 2017 #4
    Thanks guys
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