Pulse measurement for 500hhz signal

I am using USB 6251 daq card. I need to measure the number of pulses arrived with in some start time and end time. the saignal can vary upto 500k hz.Also i need the pulse arrival time for all pulses.
if i configure task for pulse width mesaurement in daqmx can i be able to measure the pulse count and pulse arrival time (upto 500khz)
Solved!
Go to Solution.

I suppose what you are reffering to is the timestamp. when you use the low level VI's of DAQmx you can obtain the signals as waveform data type, which has the initial sample time t0, the sampling intervals dt as well the sample values array Y. You can do the rest by obtaining each of the parameters in waveform pallette.
Hope this helps!
Shreyas Hebbare
Shreyas Technologies
India

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I was wondering what the percents are the percent of on the Pulse measurments.vi Default (10,50,90)%
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johnsold wrote:
Nate...,
Typically the Pulse Measurement VI used on something which looks like a rectangular pulse with a little noise, overshooot, ringing, ... Your signal is not what one would normally call a pulse by that definition.
In the first image you posted how many pulses do you count? 11? The little spikes (amplitude about 0.1 at 3.318, 3.331, 3.341, and others): Are they to be counted or rejected? Do they alwyas occur before a big spike? Some little ones are not followed by big ones but all the bigones seem to be preceeded by a small one. Is there a minimum dleay between successive pulses? Analyzing data like this can be challenging. Use all the knowledge you have about the process which generates the data to help.
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Hmm, all I had seen was sine waves before with the pulse. But, you seem to be right, rectangular pulses make a lot more sense.
Yes, I am just counting each period. I just was planning on using the pulse vi to measure the giant spikes to count how many of those occur each second. That first graph is a sound wave of a weld shorting. I want to know how often it shorts a second. I currently just have it detecting an absolute value (looking for that giant spike) and however many times it detects that I average and turn into total shorts and average shorts.
It works but it is not very elegant.
And you are correct about some of the small spikes not being followed by a big spike. That is molten slag splashing about. This short one right before the sharp spike is the sound of the arc igniting (300 Amps worth).
Can you think of any more elegant solutions to detecting the pulse? I am going to do some digging around..
Thanks Lynn!

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Solved!
Go to Solution.

Hi CracKatoA.
Take a look at the link bellow:
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Pulse measurement for 500hhz signal

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