Measuring the varying Resistance of a DC motor

I have a DAQ that uses LABVIEW. I need to calculate the changing
current going to a DC motor. I cannot measure the current directly
because it is too high for my DAQ to handle. Basically I need to
continuously monitor the varying resistance of the motor, so that I can
calculate the current the motor is pulling. Does anybody have any idea
how I could do this? I was considering breaking open an ohmmeter, but
I'm not sure how an ohmmeter works. Does the ohmmeter send a certain
voltage with certain resistances?

Thanks in advance

.

Relevant Pages

  • Re: Measuring the varying Resistance of a DC motor
    ... current going to a DC motor. ... I'm not sure how an ohmmeter works. ... It isn't motor resistance that changes. ... You keep the resistance small so your measurement doesn't disturb the system, which means you need a good low-offset amplifier in the DAQ or out. ...
    (sci.electronics.design)
  • Re: Measuring the varying Resistance of a DC motor
    ... Tim Wescott wrote: ... current going to a DC motor. ... It isn't motor resistance that changes. ... You keep the resistance small so your measurement doesn't disturb the system, which means you need a good low-offset amplifier in the DAQ or out. ...
    (sci.electronics.design)
  • How to save PC resource where using DAQmx ??
    ... The position may change although the I did not send the command to move the motor(servo motor). ... That's why I need to always to poll the DAQ. ... Can DAQ return the status I need in stead of poll by myself? ...
    (comp.lang.labview)
  • Re: Measuring the varying Resistance of a DC motor
    ... current going to a DC motor. ... I'm not sure how an ohmmeter works. ... Motor resistance does change, ... magnet decreases as the magnet gets hotter, ...
    (sci.electronics.design)
  • Re: Measuring the varying Resistance of a DC motor
    ... current going to a DC motor. ... I'm not sure how an ohmmeter works. ... It isn't motor resistance that changes. ... As a motor is loaded the back emf decreases, ...
    (sci.electronics.design)