DAQ Assistant Calibration

[BCM-CERL]

I have a PCI-MIO-16E-1 DAQ and am trying to calibrate voltage signals that I have coming in from a high voltage source using the DAQ Assistant.  The high voltage supply goes from 0 to 2000V, and the output goes through a 1000:1 voltage divider, so the DAQ sees only 0 to 2 volts.  I went through the calibration wizard and picked several points, however, after enabling the calibration, the output is less accurate than without the calibration enabled.  I am using LabView 8.5.

I also noticed that after calibrating, and going under "Properties" in the calibration menu of the DAQ Assistant, it shows "Reference" values and "Uncalibrated" values, but no "Calibrated" values.  Did I miss a step somewhere?  How can I fix this so may values are actually correct in LabView?

Thanks

[Steve_B]

Hi BCM-CERL,

The calibration procedure you described seems to be correct.

The Reference values are the values that you are using to correspond to the associated uncalibrated value. You are seeing the correct result of the calibration in the "Properties" section. The E Series cards do a linear calibration. You seem to be experiencing a situation where the calibration appears less accurate in a certain area of operation, though it may have improved in another area of operation. Our M Series cards perform a better, non-linear, calibration. You may want to look at using a custom scale which will adjust your measurement based on the scale you define. You can implement a ploynomial scale or a table defined scale to improve your readings. I ahve included links to some additional resources regarding calibration of an E Series card.

B/E/M/S Series Calibration Procedure for NI-DAQ mx
https://www.ni.com/docs/en-US/bundle/daq-mio-smio-devices-cal-pro/resource/370937w.pdf

Calibration Services
https://www.ni.com/en/shop/services/hardware/calibration-services.html