calibration of strain gages in running LabVIEW program

[PChauns]

Hi,

      I have written a program to acquire data (strain) from 10 channels. This program has to be run for 1 month. Initially, I am planning to use only 4 channels which I calibrate before starting the program. I am wondering if I need to add the remaining channels later while this program is running, how can I calibrate the gages? 

Thanks

Piyush

[Anthony_F]

Hello PChauns,

How are you calibrating the strain gauges?  Would it not be possible to always acquire the 10 channels even if there is no connection to them??  I think a little more information is needed to fully understand how you implement your calibration process and your program.

[PChauns]

Hi,

    Actually, I have a program written for 10 channels. Initially, I am planning to use 5 channels, but later I will use remaining 5. Before recording the data, I would like to calibrate the gages. So, unless I have gages connected to module (NI 9238), I can't calibrate it. I was wondering if there is any way I can calibrate the gages while using only one program. Or, I  have to run separate program for those remaining channels. Without calibration, it would be difficult to see the small changes in strain.

I hope that clears the question.

Thanks

Piyush

[Anthony_F]

I would suggest that you control the calibration of each channel via a boolean control (rocker switch, led, etc).  The control could then be attached to a case statement so that it would be possible to enable the calibration loop only when necessary.  This way you will always have 10 channels active, but only certain loops would actually be calibrating and accepting data.