TC measurements with PXI 4351 DAQ Card

(I am using version 6i of LabVIEW). I am trying to create a VI that will use a PXI 4351 Card with a TBX-68T to take 4 thermocouple continuous measurements. I am also acquiring 8 voltages with a 6030E and TBX-68 and writing them to a file. My voltage data acquisition is modeled after "Buffered Continuous Analog Input.vi" I would like to aquire voltages and temperatures in the same vi, but using different devices and accessories. (I need a higher frequency for the voltage acquisition, and more precision with the temperatures). Is there a subvi I can use to collect the temperature data in the same vi as my voltage? I don't want the thermocouple DAQ to interfere with the voltage DAQ, either.
I tried the NI435x thermocouple.vi
but I couldn't get the Built-in Cold Junction Sensor to work or figure out how to combine it with my exisiting voltage acquisition. I also got NaN for my readings, and I checked the wire connections in all the sub vi's as suggested by another solution.
Any comments would be great. Thanks in advance.

Claudia-
Thanks for the response.
Regarding the CJC- When I switch it on, the temperature readings I get are very random, roughly negative 1 degrees. (I am operating right now at room temperature, and will be using J-type TC's to measure ~43 degrees C). Also, when I use the built-in CJC, the aquisition rate seems to slow down considerably. When I use the "user specified" everything seems to be ok, including the aquisition rate.
I measured the resitance of the Thermistor on the TBX-68T and it was about 5000 Ohms, as expected.
Just to make sure: When using the TBX-68T, do I need to hard-wire a thermocouple to Channel 1/auto-zero and another to channel 0/CJC? Because I connected a TC to channel 0 right now, but I wasn't 100%
sure.
I've attached my main vi and two sub vi's that I am using for the voltage aquisition part of my project. (Note:the current measurements are just voltage measurements multiplied by the recipricol of the resistance it was measured across, ie. 10).
I would like to keep this file as is because it writes to a file exactly the way I want it to. I'd like to have the temperature aquisition with the 4351 in the same vi as the 6030E so that they both stop and start at the same time. I am just not sure how and where to log the temperature data since there will be fewer data points than the voltage data. Any suggestions? Should I write two separate files? can I somehow append them?
Thanks again. Hope to here from you soon.
Attachments:
EBlackMainDAQ.vi ‏107 KB
Save_Data8.vi ‏45 KB
Build_String_Array5.vi ‏33 KB

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多通道监测4.vi ‏199 KB

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I hope somebody could give me some help with the following and answer some questions:
Simple system description:
Labview 6.1
PCI-GPIB card
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I just want to verify that I understand your situation correctly:
An external trigger signal (A) is wired to one of your input channels (e.g. CH0) to trigger data acquisition of a second channel (e.g. CH1). Your power meter is connected to an analog input channel, which you would like to trigger with a certain rising edge at some of your sequence structure.
Problem:
During a certain point in my data-acquisition sequence structure (defined by a frame), I want to use the next occuring analog trigger signal (A) to acquire 1 value from the power meter.
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How do I configure the PFI0/Trig pin on the 6036E DAQ board individually as an INPUT?
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Claudia-
Thanks for the response.
Regarding the CJC- When I switch it on, the temperature readings I get are very random, roughly negative 1 degrees. (I am operating right now at room temperature, and will be using J-type TC's to measure ~43 degrees C). Also, when I use the built-in CJC, the aquisition rate seems to slow down considerably. When I use the "user specified" everything seems to be ok, including the aquisition rate.
I measured the resitance of the Thermistor on the TBX-68T and it was about 5000 Ohms, as expected.
Just to make sure: When using the TBX-68T, do I need to hard-wire a thermocouple to Channel 1/auto-zero and another to channel 0/CJC? Because I connected a TC to channel 0 right now, but I wasn't 100%
sure.
I've attached my main vi and two sub vi's that I am using for the voltage aquisition part of my project. (Note:the current measurements are just voltage measurements multiplied by the recipricol of the resistance it was measured across, ie. 10).
I would like to keep this file as is because it writes to a file exactly the way I want it to. I'd like to have the temperature aquisition with the 4351 in the same vi as the 6030E so that they both stop and start at the same time. I am just not sure how and where to log the temperature data since there will be fewer data points than the voltage data. Any suggestions? Should I write two separate files? can I somehow append them?
Thanks again. Hope to here from you soon.
Attachments:
EBlackMainDAQ.vi ‏107 KB
Save_Data8.vi ‏45 KB
Build_String_Array5.vi ‏33 KB

TC measurements with PXI 4351 DAQ Card

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