9221 not reading signal as expected, works while in calibration mode

[ajlapp]

I have a 9221 in my compactDAQ.  Channel 1 is connected to a 10mV per Amp current probe.  The probe reads 50mV when excited with 5 amps as expected.

The signal I've created in MAX is random and noisy when viewed from the main screen.  If I enter the calibration screen and enter a known value of 50m, the reading seems to be near perfect.

I attempted to walk through the calibration process, setting several known points but the results were always noisy when I returned to the main screen.

[griffindore]

Hi ajlapp,

The 9221 has a +-60 V range which is not software selectable as stated in the User Guide and Specifications with a 12-bit resolution. This gives a resolution of 29.3 mV. It doesn't seem that the 9221 is the best choice for measuring a 50 mV signal. Are you seeing the signal jump between 29.3 mV and 58.6 mV? If so I would say that this is expected. If you're seeing some type of noisy signal much worse than that, please attach some screenshots.