How can I messure temp on 2 diff channels simultaneous on a USB-9161 Carrier ?

[Tzaca2]

Hello, I was wondering if u can help me with a small problem, with my USB-9161 Carrier. I intend to messure temperature with two thermocouples on 2 physical channels of the device, in the same time. Do i need a special VI for this operation ? As far as I have seen the VI promps me to select a single phisical channel. Can I record data for both thermocouples? Thank you so much

[TrottM]

Hi Tzaca,

Can you clarify which module you are using within your 9161 Carrier. The 9161 does not contain any data acquisition functionality by itself but enables certain C-Series modules to interface with your PC via USB. For Thermocouple measurements the ideal module would be the NI 9211 for your purpose, however other modules will work that contain the appropriate signal conditioning. I.e. Cold Junction Compensation (CJC).

Assuming you have an appropriate module however you can record from both thermocouples using a LABview programming technique called synchronization. I have found an article on the NI Developer Zone website that explains this principle well using LabVIEW 2010. Take a look at this and see how you get on.

Easily Synchronize Your Measurements in LabVIEW 2010

http://zone.ni.com/devzone/cda/tut/p/id/11549

If you need any more assistance with this let me know how you get on and I'll try and help you further.

Matt T

[Tzaca2]

Thank you very much for your answer ! I will check the article you sugested, and see if i can resolve the problem. The module i am using is indeed 9211. I think its about the software, i am using a Labview 7 VI, maybe something newer is needed.

Thank you very much again!

Stancalie Andrei

Assistent Researcher

National Institute for Laser, Plasma and Radiation Physics 

www.inflpr.ro

 

[TrottM]

Its not a problem. Glad I could help. I have had a look at compatability with LabVIEW 7 and support for the DAQmx vi's appears to have begun in that version. I found this in the Knowledge Base and the link is below. As far as I know all functions referenced in my previous post should still work.

NI-DAQ and LabVIEW Version Compatibility (for Windows)

http://digital.ni.com/public.nsf/allkb/B0D5630C0A50D5C6862578E800459248?OpenDocument

Hope this helps.

Matt T