SCXI-1122 Thermocouple System

[oj]

I have thermocouples hooked into a SCXI-1122 module. Using virtual channels in MAX, I am able to see all the voltages correctly. Also, by specifying each individual thermocouple in LabView (e.g. ob0! sc1! md4! 1) I am able to see the voltages correctly. When I read more than one thermocouple using the syntax (ob0! sc1! md4! 1,2) I am able to see the correct voltage for only the first thermocouple in the list. I would like to use bulk addressing to read all 16 thermocouples at once (ob0! sc1! md4! 0:15) but it does not show any voltages correctly. I suspect this is a simple configuration problem. Any insight?

[Filipe A.]

Hello;

You are seeing incorrect values probably due to a too low interchannel delay. If you don't specify the interchannel delay of your application, NI-DAQ will set the lowest value allowed, and sometimes that value is too low for the application.

You can change the interchannel delay value at AI Config.vi.

Hope this helps.
Filipe A.
Applications Engineer
National Instruments