Thermocouple Readings from CRIO

Hi,
I am fairly new to working with Compact RIO and I am having problems with thermocouples that I have connected. My setup has two thermocouple modules, the NI 9213 and NI 9211.
I have connected a Type K thermocouple (one each) to both of the units. I have used the FPGA Target vi to read from the Thermocouple channels together with the CJC and Autozero values of both the modules. I also have CRIO vi that references the FPGA vi and then uses the values and feeds them to the "Convert Voltage to Temperature.vi". I have attached screenshots of both the vi's.
The problem is the output I am receiving is -2 or 1 degree. When I touch the thermocouple the value increses to around 5 or 8 degrees. The room temperature is around 24 degrees.
Can someone please help with where I am going wrong.
regards
Harshil.
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Attachments:
FPGAvi.jpg ‏51 KB
cRIOvi.JPG ‏60 KB

Hi Harshil,
Which cRIO controller and back plane are you using? As long as you don't have a 9002 or 9004, then you can get away without programming the FPGA with CompactRIO Scan Mode, which will calibrate and scale your temperature channels for you.
If you have a chassis that only has a 1M gate FPGA, you can still use scan mode for your TC modules, see this KB:
http://digital.ni.com/public.nsf/allkb/122E971F52FD081A86257500007A046C?OpenDocument
Using CompactRIO Scan Mode with LabVIEW:
http://zone.ni.com/devzone/cda/tut/p/id/7338
Kurt
Kurt
Join the LabVIEW Real-Time Developers Group

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Thermocouple Readings from CRIO

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