Low frequency measurement (1 to 5 Hz) issues - Reg

[sathishkumar]

Hello All,

i am facing a problem in measuring Low-Frequencies in the range of 1-5 Hz. I am using VIs used for pulse-width measurement and the card is PCI-6031E. i am generating frequency using PCI-6013 card.

Actually i am trying to develop an application for measuring the speed (RPM) of the motor which runs very slowly. so if  i miss one pulse  per second also, when i multiply that with 60 it will be big error.

So if any can give me a solution that will be big help to my issues.

Thanks.

[e-Cash-Money]

Hello sathiskumar,

I'm not sure what you mean by missing a pulse but I think what is happening is that your counter is rolling over and starting to count from zero again.  Every time the counter rolls over, it will output a pulse.  You can connect this signal to another counter and count how many times your first counter has rolled over.  That way, if you don't receive a pulse on your first counter before your counter rolls over, the second counter will have a record of how many times this has happened.

I hope this helps!