Multifunction DAQ

Showing results for 
Search instead for 
Did you mean: 

I want to measure microvolts using NI 9219 (Universal DAQ) using labview

Go to solution

Dear community members, 

I am using a  Cdaq 9188  along with NI 9219 for acquiring voltage from the heat flux sensor which is of microvolt order. Now my question is it possible to measure the microvolt range in the foresaid card. I am getting some value don't know whether it is correct or only noise. And also the output from the sensor is fluctuating too much, although the heat flux is steady. Is there any way to have a steady output?
Kindly help.
If any other info needed please ask.

0 Kudos
Message 1 of 4
Accepted by Chandan100

You should be able to measure uV values using this card in the 125mV range same as the one used for Thermocouple. Below are the accuracy specifications.



Semiconductor Validation & Production Test
Soliton Technologies
Message 2 of 4

Hello, Santo_13,

Thanks for your suggestions.

My measurements are in 1 microvolts order, it seems like it is difficult to measure but one thing I would like to mention that it was showing readinds but very flactuating. I also have 9205 is it feasible measure the same?

Thanks in advance

0 Kudos
Message 3 of 4
Accepted by Chandan100

For a 1uV measurement, the largest error is going to be the offset error which is +-120ppm (25C) of range, which calculates to 120e-6*125e-3 = +-15uV. If your measurements are noisy, I would suggest using the high-resolution sampling rate or implement a software-based moving average.


And for the 9205, you will not be able to measure 1uV either, even in the 0.2V range, the resolution is 6.57uV/LSB (this means, the measurements are always a multiple of 6.57uV)



If you are looking for better accuracy then your only option is to use a DMM (6.5digit or higher)



Semiconductor Validation & Production Test
Soliton Technologies
Message 4 of 4