What Is the Accuracy of NI 9222?

Updated Dec 26, 2019

Reported In

Hardware

  • NI-9222

Issue Details

I have NI 9222 C Series Module. How is the accuracy of this module calculated?

Solution

Refer to page 6 of the specifications document  for gain and offset error information.

We can then plug in these values in the formulae specified in this document to reach the accuracy values depending upon the device calibration status and test environment.



Using the above table, accuracy of NI 9222 at 0V reading for a calibrated device, operating at maximum temperature range is (ignoring noise uncertainty):

Absolute Accuracy =± [(VoltageReading x GainError) + (VoltageRange x OffsetError) + NoiseUncertainty]
                               = ±  [(0 x 0.2/100) + (10.6 x 0.01/100)]
                               = ±  1.06 mV 
 

Additional Information

Calculating Absolute Accuracy or System Accuracy - This link can be used for calculating the accuracy for C Series modules (CompactDAQ and CompactRIO based) based on gain, offset error and noise. 


LSBrms Unit Meaning for the System Noise Specification - Some noise specifications are in terms of LSBrms. This KB explains the meaning and how to interpret the same.