LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

Finding the absolute (bits) ADC value from DAQ

OK, so i give you some background knowledge:

1. Most NI multifunction DAQ devices use an SAR ADC with 5V supply. The signal is amplified to that range automatically as there DAQmx driver configures the preceding amplifier. That means, if you configure +-10V, the amplifier would attenuate the signal by 2 (or amplify by 0.5).

2. Your scaling could be a table, a simple linear equation or some polynom. As you post in the LV forums, i would expect that task to be implemented in LV. Use the scaling methods in the Mathematics >> Interpolation or write your own scaling subvi. For creating a table/polynom, you can use the Mathematics >> Fitting functions.

3. Many Multifunction DAQ device from NI use a mux for the AI. So all AI are converted using a single ADC. In that case, you have to make sure that your signal source is of low impedence as otherwise, you will run into crosstalking.

 

Norbert

 

EDIT: Just checked with the manual for the 6230. It states real valuable information for you in chapter 4.

Norbert
----------------------------------------------------------------------------------------------------
CEO: What exactly is stopping us from doing this?
Expert: Geometry
Marketing Manager: Just ignore it.
0 Kudos
Message 11 of 11
(120 Views)