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How do I read cjtemp using DAQmx task?

Im using labview 7.1 DAQmx 8.8. with SCXI 1000 chassis, 1600 digitizer module, 1102 module with 1303 interface for temperature and voltage measurements, and 1520 module with 1314 interface for strain measurements.  I plan to measure strain, temperature and some voltage inputs.  I would like to read the CJC of the 1303 board and use it in thermocouple temperature calculations.  

 

IN MAX: When I open test panels for the 1102 module, Mod4/_cjTEMP is a channel that can be selected and tested but when I create a DAQmx task cjTEMP is not listed as a physical channel. 

 

How can I configure my system to read cjTEMP as part of the physical channel list in DAQmx Task

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Hi DaveF,

 

The cjTemp channel is an internal channel and cannot be accessed in MAX with a DAQmx Task. In order to read this channel you will need to enable Advanced Terminals in LabVIEW.

 

The document below goes into more detail about this:

http://digital.ni.com/public.nsf/allkb/5BD53EE380E01CA18625766200657A79?OpenDocument

 

Also, to enable Advanced Terminals:

http://digital.ni.com/public.nsf/allkb/DF48BC8CFFA1F6CB86256F5D007EA11A

Sunaina K.
Product Marketing Manager for CompactRIO & TSN

Making the intangible, tangible
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OK, I can do that.

 

Do I need to configure all other channels this way?  Is there a way to configure all other channels in a DAQmx task and programaticlly modify the task to configure one channel to read cjTEMP?

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You can select multiple channels in one DAQmx task for Analog Input.  If you wanted to read the cj temp, and channels 0-5, your physical channels selector would look something like:

 

 

cjtemp.png

National Instruments
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[duplicate]

National Instruments
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Thanks, that seems to work fine. 

 

So, now that I have the cjtemp value (volts), how do I convert it to temperature (deg C)?

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The section titled Temperature Sensor Output and Accuracy in the manual outlines how to convert the voltage reading to a temperature reading.

Sunaina K.
Product Marketing Manager for CompactRIO & TSN

Making the intangible, tangible
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Also, an easier way to scale cjtemp data is to use the Analog Input >> More >> Temperature Built-In Sensor version of the DAQmx Create Channel VI: AI Temp Built-In Sensor

 

Brad

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Brad Keryan
NI R&D
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