waveform peak detection

[Nick_F]

Hi All,

I am using the waveform peak detector to detect the number of peaks in a signal. Lets say I use as input a sine signal with a frequency of 1kHz. I want to be able to count all the peaks in this signal during a period of time of 30 seconds and to display them in a counter. I am not sure if I need to use a timed structure, or to use initialize/end of data inputs of the waveform peak detector component. I would appreciate some details about how to do this.

Regards,

Nick

[Andy F.]

Nick,

Are you acquiring the data and analyzing the peaks on the fly?  Do you have an approximate idea of what the peak value will be?  In any case a resolution of 1 ms is about all you will be able to accomplish on a windows machine, even when using a timed loop, which is slightly better, determinism-wise, than a while loop and a wait function.  Are you analysing the data in 30 second sections or trying to count for 30 seconds and then reset.  The Waveform Peak Detection will probably work best if you are taking 30 seconds work of data and analyzing that.  Do you have any specific questions about architecture or how to use the function?  A sample VI and some more details would be very beneficial.  Thanks!

Andy F.

[Nick_F]

Hi Andy,

I am using a Windows machine and the resolution of 1ms is good enough. I need to display the number of pulses after 30 seconds interval. I do some sort of analysis of the data and it would be good to be able to display the counts as they increment during the 30 seconds interval. It would be excellent if you could provide some information about how to use a timed loop and the peak detector, I have very little experience with Labview. I tried a few things but nothing worked. I added here a simple vi where I put the timed loop around the blocks. But I don't know how to setup it.

Regards,

Nicolae