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How to record Temp. Vs time (s) to excel file?

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Hello

I am farily new to LabView. I had been banging my head against it for about a week and now I need some guidance. I have SCXI1102 with PXI-6289 to record temperature.

So far I have made a very simple block diagram to read the temperatures. But I need to get it to record it. I am shooting for Temp. vs. Time(s). I want temp measurement every second recorded. I used DAQ Assist to graph it and also show it in text. I have a time delay of 1 second in while loop. Can anyone guide me on how to get temperature recorded in data file, hopefully excel file?

 

I have attached an image of my block diagram.

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There are plenty of examples for SCXI for different sensors, at Labview>>Help>>Find Examples. It would be easier way to get started. The express vi that you are using is not a very efficient way of data acquisition. Try to use Daqmx functions. Also, the to add delay in loop use either 'wait' or 'wait until next ms multiple' from the functions palotte. And the amount of delay should be less than one second, assuming that you want to acquire data atleast at few Hz. 

  I just used one of those example vis and modified it for excel record.

 



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Thanks for your reply. I finally have something working and logging the data. I don't know the difference between DAQ assistant and DAQmx. I used DAQ assistant based on some tutorials I found. I need to take the temperature every second. I just want to find out how long does it take to reach to certain temperature. I have no experience in data acquisition, in general so I am trying to learn everything from scratch. Thanks for your help. Cheers
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All that you really needed to do was add a Write to Measurement File function. That should not have taken a week. And, for future reference, never post just an image when you are using the DAQ Assistant. All of the information is hidden in the assistant and you need to post the actual VI or a snippet.

 

p.s. the example posted by odessy does not record any timing information.

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Thanks for your reply Dennis. Unfortunately, I am new to LabView and DAQ in general. It took me some time to understand this stuff. I will post the VI as soon as I get access to it.

Currently, I have "Write to Labview Measurement File.VI" taking the data, however, is there anyway I can also have it mark the time stamp for each row. Its logging 2 channels in 2 columns, leaving the first column empty. It would be helpful if I can have it mark time stamp for each measurement. 

 

Also, I have a waveformgraph displaying my temperature, is there any way I can have it plot each point as it acquires? so after I can see the curve patterns as the test is going. Right now its just scrollig through. 

 

And what do you think about using time delay vs wait ms VI, if I am taking measurement every second?

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Need to see the VI to know why you have an empty time column.

 

There is no difference between the Delay function and the Wait (ms) function except the Delay specifies time in seconds and it has error in/error out connections. The Delay function uses the Wait(ms) so saying use one and not the other is silly.

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thanks for great information.

 

Here is the VI. I would appriciate your input.

 

 

Thanks

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Message 7 of 9
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You configured the Write to Measurement File to have an empty time column. Double click on it and change it.

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Dennis is right, there is no difference between Time delay express vi and 'wait' function. I, however, have never seen using time delay express vi used in data acquisition application before and was under the assumption was, everything blue (express vi Smiley Very Happy) was bad programming hence I recommended op to use other timing functions. My apologies for misinformation!

 

 

-Nilesh



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