01-08-2014 01:46 PM
In the NI TC-4353 Calibration Procedure ,under "Terminal Block Temperature Accuracy Verification", step 3 reads:
3. Acquire a CJC temp0 value.
a. Set the timing mode to 1 (High Resolution).
b. Configure the timing properties for a finite acquisition with a sample clock rate of 1 S/s and 30 samples per channel.
c. Start the task.
d. Average the temperature data and record this value as cjc_temp0.
What software is used for this step?
01-09-2014 02:12 PM
Hi rcathrin,
The steps will need to be followed within DAQmx.
Please assure that you have DAQmx 9.6 or later. As stated in the Calibration Manual:
"Calibrating the NI PXIe-4353 and TC-4353 requires the installation of NI-DAQmx 9.6 or later
on the calibration system."
Hope this helps you move forward with your application.
01-09-2014 03:25 PM
Thanks MJ,
My calibration work station has the following software loaded:
Calibration Executive 3.4.1 - not useful for PXIe-4353 w/ TC-4353
MAX 5.5.0 with DAQmx 9.7.5 and LabView Run-Time 8.2.1 thru 2013 - I do not have a development version of LabView on this computer
AcqCJC Temperature.vi - downloaded from http://forums.ni.com/t5/PXI/PXIe-4353/m-p/1656960/highlight/true#M9522 and compiled on a development work station with LabView Pro
PXIe-4353 Accuracy Calculator - downloaded from http://digital.ni.com/public.nsf/allkb/575CC9377C0ECD1086257A4F00579364
In Measurement and Automation Explorer, I can launch "Test Panel for the PXIe-4353" and read the cold junction channels, but only as voltage. If I create a "Task" cold junctions are not available. So, MAX does not seem to be the software refered to in the TC-4353 Cal Procedure.
The PXIe-4353 Accuracy Calculator may be part of the equation, it does have most of the setting called for the in the procedure, but still does not seem to be the right answer.
The Acq CJC Temperature apears to read the cold juction thermistors OK, but only one at a time and no settings to match the proceedure.
Additional question, the procedure calls for a parallel feed of all 32 channels using Type "E" TC Calibrator. Could this be done using another TC type if the min/max limits were adjusted to match, say type "T" thermocouple?
Our facility is installing over 500 PXIe-4353 w/ TC-4353 channels this spring, so my cal lab needs a working solution soon.
Thanks for you help,
Ross Cathriner
01-10-2014 05:59 PM
Hi Ross,
It seems like the Terminal Block Temperature Accuracy Verification process needs to be followed in the LabVIEW development environment with the use of code similar to the one in AcqCJC Temperature.vi along with property nodes.
Using another TC calibrator should technically work but I would recommend using Type E as recommended in the manual.