LabVIEW

[Mrssss]

Hello everybody.

I have a problems with my VI. I need to measure a frequency of signal. While I gauging I have a correct value, but after reset of Elapsed Time sometimes I take a peak. I can't eliminate that. I'm almost newbie in Labview. I will be thankful for any help with that.

Lukasz

[ThiCop]

Hello Lukasz,

Do you have a data log of how your acquired data looks like?

Or do you have a screenshot that illustrates the unwanted behavior?

[Mrssss]

Hello,

Thank you for you answer. During the gauging I observed perodically a peaks (see attached screenshot). This VI measuring the frequency of simulating signal like real from analog card.I think it's something wrong with "Elapsed time" function or loops. I can't deal with it. Elapsed times is a internal clock (count a 3 second, after that reset and count again). I will be thankful for any helps.

[johnsold]

Your problem occurs after you reset the Elapsed Time VI. On the next iteration you divide by a very small number.

Look at the modifications I made to your VI.  Run it until you see one or two of the peaks. Stop.  Then look at the three arrays until you find the point where the peak occurs.  Notice that the denominator values may drop by a factor of 1000 or more.

Lynn

[Mrssss]

Thank you for your reply. I tried to remove/ cut-off a unwanted peaks but I can't gave a good results.

[johnsold]

Exactly what is it that you are trying to calculate?  I cannot offer suggestions without understanding what you are trying to do.  It was clear that dividing by a small number causes the peaks.  What shoud you divide by  to get the results you want?

Lynn

[Mrssss · Accepted solution]

Hello Lynn

Sorry for my absence. I need to measure a frequency from simulating signal. (frequency from 0 to 50 Hz). Everything is okay, excluding that peaks. I can see a frequency in "Czestotliwosc". I count a Falling or Rising edge and compute in knowing peroid of time. Elapsed time is a function of "Windows timing" in this VI.