automatic snesor calibration problem

[ivy037]

Assume the DAQ has no error at all, now I want to calibrate the pH sensor itself AUTOMATICALLY. my idea is to let calibration solution flow through it. If the measured voltage is not equal to the known voltage for that calibration solution, there is an +or - error. I want to record this value SOMEWHERE(how), so that next time when the pH sensor measures other solution, my VI code will offset the measured voltage by using that stored error value.

Can my idea be fulfilled?

I know how to create scale using this turtorial  http://digital.ni.com/public.nsf/allkb/3F6558112FD2C776862575B5004F7F87?OpenDocument

but that's manual input

[CertifiNATEtion]

Hi Ivy037, 

You should be able to do what you have described by writing the value to a file, and then performing the math on the next measured values. You can find examples of how to read and write to a file in the LabVIEW example finder (open LabVIEW, click on the Help menu, and then click 'Find Examples')

If your device supports it you can also do a self calibration in MAX. 

Here is a useful document on calibration procedures:

http://ae.natinst.com/public.nsf/web/searchinternal/305db655c3c5c7628625710a005198f7?OpenDocument

Please let me know if you have any further questions!

-N