large frequency readings using the DAQ Express VI: Counter

[epedersen@casconpump.com]

I am currently using a 6341 DAQ and trying to read a speed signal from an electric motor (5 vdc square wave) using the DAQ assistant express VI.  I can read the correct frequency of the square wave, but periodically get a reading of a million or more for the frequency.   Given the fact that the 6341 can only sample at 500 k Hz, i know that frequency cant be real.  The signal on an external O-scope shows the signal to be fairly clean.

Does anyone know why i may be getting the high frequency readings?  and at what voltage does the counter trigger at, when counting the voltage rise of each wave?

Thanks

Erik

[G-IV]

Hi Erik,

Is there any chance you could post your code?  It will make helping you out a lot easier.

You can upload the code or a snippet (link will open in a new page).

Regards,

G-IV

[epedersen@casconpump.com]

Thank you for offering, but i just got it working using the digital filter of the DAQmx channel property.   For anyone trying this, just expand the express vi for the counter and add the digital filter up stream of it.  This can be found in one of the other posts on frequency input troubles.

Thank you,

Erik

[G-IV]

I'm glad to hear that you got it fixed!

Would you mind putting up whatever link you used that helped you figure this out?  Other users that come across your post will likely find that helpful.

Regards,

G-IV