SCXI-1112 thermocouple with Autozero.vi

Please the following doubt I have on the example program "SCXI-1112 thermocouple with Autozero.vi".
In the vi's first sequence ground readings for each channel is found out and it is available in a 1D array. Each element in the 1D array corresponds to each channel's ground reading. These zero readings of each channels are to be substacted from each channel's subsequent data. But it is not doing so. In the second sequence since a column is indexed (which corresponds to one channel data) actual substraction is taking place between a channel's data and all channels ground readings available from first sequence. which is wrong.
Kindly clarify the above doubt.

Greetings,
You are correct. This example needs to be modified. The array of offset data should be indexed so that only one scalar value is subtracted from each element in the array of data from one channel. I have attached a modified version of the example.
Good luck with your application.
Spencer S.
Attachments:
SCXI-1112_Thermocouple_with_Autozero--Corrected.vi ‏147 KB

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SCXI - 1112 wrong value with two channels

Hi,
I work with VI logger to acquire temperature with 1000DC chassis and SCXI1112. My problem is when I use more than 1 thermocouple, temperature is wrong : for exemple, I start an acquisition with two thermocouples connected and if I disconnect one, the value of the other change (not always same step).
My measures are made on PCB with potential : this can be the reason of my problem ?
Is there any solution to solve this ?
Thank you for your help
Regards
Michael

Hello,
Your problem seems quiet strange cause you're using 2 (or more) different
channels. It may be the consequence of the fact that you just touch the cold
junction compensation when you unplug a thermocouple. Or it might also be
linked to the fact that you bring cold air when you unplug it...
What's the temperature modification range? 0.5° ? 0.05°?
Regards
Richard Keromen
National Instruments France
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Problem to install modul SCXI 1112 with a 1000DC chassis

I want to install the module SCXi 1112 with the chassis 1000DC but when I test the chassis with NI Max, it don t find the module.I connect the chassis to a MIO 6025E. One precision, I have control the connection between the two elements and the autodetection don t find the module
warning message Failed to find Slot 1 is empty

Mous,
The first step is to make sure that the NI-DAQ driver is installed properly and that your DAQ board (6025E) is working properly.
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http://www.ni.com/pdf/manuals/322476a.pdf.
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Nardelli,
Could you provide some additional details concerning your setup? The SCXI-1112 has a maximum sampling rate of 333 kS/s. Thus, most likely, the program that is controlling the hardware is determining the sampling rate. Which development environment are you using? What type of programming structure are you implementing with regards to the SCXI-1112? Single-point acquisition (software timed)? Buffered acquisition (hardware timed)?
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Hi,
I have SCXI 1112 thermocouple input module, SCXI 1180 feedthrough panel , and a SCXI 1302 terminal block connected SCXI 1000 chassis with SCXI 1349 adapter. I am trying to measure voltage by using SCXI 1180&1302, and temperature by 1112 module at the same time. When chassis is on SCXI 1112 runs without a problem; however, voltage reading coming through SCXI 1349 makes no sense (plus I can't run them at the same time, LAbview gives an error). While the chassis' power is off, it is the other way around, SCXI 1349 runs smoothly.
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One piece of the puzzle you left out is the DAQ card being used in the host computer.
Without looking at some specifics on the SCXI cards/connectors you are using, I will comment you must be careful when you are using an 1180 feedthrough module. Keep in mind, the SCXI chassis is Signal Conditioning -- it's nothing without the DAQ.
I would recommend you back up a few steps, simplify the setup and test each input channel from MAX -- making sure you aren't overlapping channels between the 1180 to the DAQ and the SCXI chassis. Remember, most data from the SCXI chassis comes in on a single channel of the DAQ through the 1349.
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Suresh,
I assume you will be using LabVIEW to perform the calibration (let me know if I am incorrect). The LabVIEW help for "SCXI Calibrate.vi" (Functions >> Data Acquisition >> Calibration and Configuration) describes its use for both internal and external SCXI calibrations.
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Hi gq,
Could you please provide a screenshot of the
way you are configuring the task, as well as what the data looks like
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Suresh,
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-Try using a Producer/Consumer architecture. This architecture uses queues and splits the aquisition with the post processing.  Here is a link to how to set up this architecture and some information on when to use it.
Application Design Patterns: Producer/Consumer
http://zone.ni.com/devzone/cda/tut/p/id/3023
Message Edited by Jordan F on 02-06-2009 04:35 PM
Regards,
Jordan F
National Instruments

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Dave,
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Attachments:
testit.vi ‏74 KB

Steve1,
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