How do I set strain gauge resistance on 9237

[CharlieM]

This link should be helpful  

[rex1030]

So does that mean that the project has been tested? You guys wouldn't put it on the support site without testing it on a crio system hooked up to strain gauges would you?

[CharlieM]

The code was tested with a 120 Ohm gauge and a quarter bridge completion accessory.

[rex1030]

Charlie , your calibration example works flawlessly. I can't thank you enough. Your infinite patience is refreshing.

Can you pretty please, with a cherry on top, modify this example to log data continuously? Please? I have been struggling for a long time (since I started this thread) trying to write a VI that aquires continuously. I keep getting invalid data from the module with the programs I have written. I have opened a few support threads and the app engineers keep telling me that my code looks fine. Which, of course, makes no sense because it doesn't work. Even if you just posted something that was unofficial it would really help me out. I am using the same configuration you  programmed the "Shuntoffset" example for. I am using a 120 Ohm gauge and a quarter bridge completion accessory.

I don't want anything amazing, I just want to be able to calibrate and then log data continously. I feel that the example VI for this module should be doing that already. NI saying that the reason they didn't provide one is because every person's situation is different is a cop out. You know perfectly well that any differences in the system could be user selectable controls that change the VI. Anyways, none of that is your fault of course charlie. I guess I am just venting my frustrations about my troubles.

I really appreciate all your help so far. Thanks again.

Sincerely,

Kyle

[Bassett_Hound]

Kyle,

Please try the following example.  You'll have to modify it from the 9233 to the 9237 but it should be as simple as switching the module in the project and ensuring the IO are named the same.  Any chance you have the Service Request numbers for the issues you where having?  It would be nice to be able to follow up the the Engineers that were helping out to make sure the information is received by everyone.

Regards,

Bassett Hound

[Jimmy P]

I have been using the example program in this discussion forum and it looks like it works great. The offset and null compensation give me correct values as far as I know. I do have two questions:

1. In the "NI 9237 Example for Shunt Cal and Offset Cal" under the Developer Zone, a note states that "You should perform an offset null compensation just before you perform a shunt calibration." Can someone explain to me how to do this?

2. When I run the calibration program multiple times in a row, the offset values seem to increase little by little. Is this typical?

Thanks,
Jimmy P.

[pauloeduardo@maxioncr.com.br]

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Message Edited by pauloeduardo@maxioncr.com.br on 03-04-2008 12:11 PM

[pauloeduardo@maxioncr.com.br]

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Message Edited by pauloeduardo@maxioncr.com.br on 03-04-2008 12:11 PM

[pauloeduardo@maxioncr.com.br]

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Message Edited by pauloeduardo@maxioncr.com.br on 03-04-2008 12:12 PM

[pauloeduardo@maxioncr.com.br]

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Message Edited by pauloeduardo@maxioncr.com.br on 03-04-2008 12:13 PM