usb 6008 + analog input stuck

[-SK-]

Hello,

I have just started experiencing a problem with a usb6008 that I have not seen before. When I run my VI, the values read from the analog inputs Ai1-Ai3 are -9.8, -10.2, -10.2 respectively. Those values are constantly read no matter what I put on the pins.The correct voltage (0-5V) appears on the pin when measured with a multimeter, but Labview is interpreting them incorrectly. 

I have been developing this same software for 3 months now, and I have never experienced this problem.  I have made no changes in the last month that affect the way the program gathers data. I use DAQMX get analog input 1D 1 sample Nch. to get the values I am sampling.

What causes this, and how can I fix it?

[BCho]

Hey -SK-

What type of signal are you measuring and what type of signal did you set up for DAQmx task? If you have a RSE signal and are set-up to measure a differential signal you could see the 'railing' performance that you are. If do indeed have a differential signal, you may need to include bias resistors with your set up. Take a look at this Field Wiring Diagram for a little more information on RSE and differential signals.

Hope this helps.

-Ben