Hello,
For troubleshooting bad readings, probably the first thing to do would be to check the board's configuration.
Is it configured in differential mode? Differential mode is the most recommended mode for thermocouple readings. When using differential mode, just make sure to connect the positive lead of the thermocouple to ACH0 (for example), and the negative to ACH8.
Once you have all the signals connected to your DAQ board, try running a MAX Test Panel. I usually run it using Continuous Mode. Before starting the acquisition, check the input limits in MAX, adjust them according to the input signal so that the board applies the appropriate gain.
Finally, create a Virtual Channel (by taking into consideration the thermocouple type). Are you re
ading the correct temperature? Is the CJC in your terminal block enabled? It's always easier to compare the temperature than the millivolts readings.
I hope these tips help. Good luck with your application!