TC01 Spreadsheet Logger tweeks

[darbyln]

I recently purchased the USB-TC01 device.  Before purchasing I called and asked to verify that the sample app will log temp with at least 2 decimal places.  I was told that it will.  After receiving the product I found that the app that comes with the device only logs 1 decimal place.  I know the USB-TC01 has more resolution but the app just rounds to the first decimal place.  

The app that comes with the device is very good but will not log 2 or more decimal places.  Here is what I need and the app can do.  The sample app is an executable file not a VI. It allows you to start and stop logging without restarting the app. It clears the data from the graph each time you restart. It allows you to select the thermocouple type in the app. It allows you to select F or C and you can save the log file to any path you wish.  There is a sample VI on the NI website that they imply is the same as this included app that you can modify but it is not.  I have modified this VI to do a couple of the things that I need but I am new to LabView and I am not sure how to do a few things.

I want the data and graph to clear each time I click the start button.  I have it clearing the data but my problem is that when the data is saved to a log file only the last entry is saved.  I guess it is clearing the data right before saving.  Not sure how to do this.  

Also not sure how to get a drop down combo box to allow me to select the thermo couple type and C or F.  

Any help you can provide would be apprechiated.

[jcarmody]

[EDIT] Sorry, I posted before fully understanding your request.

[darbyln]

If I wanted to scrap this idea and just program something in VB .net could I do that?  I guess I would need DAQmx to get the .net object.  Do I need to purchase a license to use this?  If so is there any other way to do this?  

[jcarmody]

Don't scrap this idea, you're not far from a solution.

Try what I've attached.  I've modified the DAQ Assistant Express VI and the main,  Look at the changes I made to the settings in the Log Measurement Data Express VI.  I think I have what you described in your first post.

BTW, VB.net = 😛

[darbyln]

Thanks for the help.  I tried to run your example and I got the following error.  Not sure what is wrong.  

Do I need to tie the two projects together?  I tried to modify my project to look like your example and it tries to save the log file every second and never collects any data.

[jcarmody]

I can't duplicate that error.  Did you get it by running the files I attached?

Here's something I did last year, try it and see if it'll work.  Your problem might be in the physical channel of your device.

[darbyln]

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@jcarmody wrote:

I can't duplicate that error.  Did you get it by running the files I attached?

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Yes, I got this error was when running your VI. I got MY app doing everything I need except allowing me to set the Thermocouple Type and F or C.

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@jcarmody wrote:

Here's something I did last year, try it and see if it'll work.  Your problem might be in the physical channel of your device.

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I will look at this example too.  

[jcarmody]

You could wrap your DAQ Assistant Express VI in a Case Structure with an Enum selector, duplicate it in both cases and configure it to read Fahrenheit in one and Celsius in the other.  Maybe?

[darbyln]

I figured out the problem with the first example you sent me.  I had the wrong "physical channel" selected.  Now it works fine.  

One remaining issue.  I used your modDAQass.vi and it works good with one small problem.  When I stop logging, it saves the data but then when I start again the graph clears and starts fresh but the log data has both sessions.  How can I clear the data from the previous capture and start fresh with every start button press?

[Kimberly_Wenger_Austin]

Hi darbyln,

I was able to open and run your VI and I am not exactly sure what you would like to happen with regards to clearing the data that you are logging.  I am assuming you are referring to the output of the Export Waveforms to Spreadsheet file to be the logged data.

To show you what I did, I will let you know all the steps that I took to try and diagnose the issue.  When I run the VI the way it is and press Start, it will log until I press Stop. From there, if I press Start again, and then Stop, it prompts me on whether or not I want to replace the current log of the file. If I click yes, then it will override the previous data entry.

If you would like to have all the data files logged together, you can simply add a constant to the "append to file" node of the "Export Waveforms to Spreadsheet File.vi" and change it to "True".

Thanks!

Kim W.