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Sound and Vibration pallet is only for ...

Examples are simple code to show a simple concept.  You won't find any examples of complete applications that perfectly suit your particular needs.  That's why programmers get paid! Smiley Wink

 

You need to write out your application as a flowchart or state diagram.  Break it down into steps you can understand and code as stand-alone modules.  Then combine it all together in a state machine that reads the physical data,  does the analysis, sends new parameters, then loops until it passes the criteria.  This is not a trivial design.  We can try to help but you probably won't get a complete "example" posted for you.

 

BTW, if there's no reason to start a new thread you should just keep posting in your original one.  Jumping around is confusing and frustrating to those trying to help you.

LabVIEW 8.5.1 - 2019 Pro Dev
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I am reading the voltage analog signal from DAQ which is linear to the acceleration detected by the sensor. I don't have any NI sound and vibration toolkit but how can I convert this wave form into a meaningful Acceleration parameters. I am new to labview and first time using USB 6008.  

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I am doing a continuous reading operation by using USB 6008. Though, it was worked well yesterday but suddenly encounters error 200279. I read lot of threads on forum and I am following each one as they said but still I am in error. My code is simply a DAQ assistant that reads data and display it in graph continuously and these are in a while loop. Though, I have followed the formula that samples to read is 10% of rate. 

 

I increased both combinations many time but still error encounter after few seconds of run. Hope some one help me.

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you can see an oscillation in your waveform - this is likely the back and forth vibration from your pump as recorded by the sensor. 

you need to scale from volts to acceleration (g) and should use the sensitifvity (typically expressed in mv/g) to scale to g.

you will want to run the data thru a low pass filter to remove the high frequency noise in the signal.

from there you can use a FFT or tome detection to determine the fundamental frequency of vibration and its amplitude. 

 

Preston Johnson
Solutions Manager, Industrial IoT: Condition Monitoring and Predictive Analytics
cbt
512 431 2371
preston.johnson@cbtechinc
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Hi,

        Thank you so much for your suggestions but I may guess I am no need follow that way. You can see the below figures for idea. One figure is of with noise(came from some mechanical touches) and other no noise(because I adjusted the stoke length manually). Now, I need to run a continuous program that can be like this.

1) Acquire the signal into labview(it's done now)

2) see the noise with software and if noisy, adjust the stroke by serial and again acquire the data and verify, if it is still noisy follow the same step as before until its get normal picture as shown.

 

How can I differentiate this, where are those function in labview. First time I am making DAQ program, hoping for some tips.

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Pictures are here.

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the fast fourier transform (FFT) will be your friend. 

Preston Johnson
Solutions Manager, Industrial IoT: Condition Monitoring and Predictive Analytics
cbt
512 431 2371
preston.johnson@cbtechinc
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Message 17 of 25
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It looks like you have about a 10:1 amplitude difference between the good and bad.  Set a threshold around 0.7 to 1.0 V.  Above that = bad, below = good.  You will probably need to refine the process when you see how much variation you have from pump to pump, but this shoud get you started.  As Preston suggested an FFT would give you another means of discrimination because the impact will produce large amounts of high frequency energy that is not present in normal operation.

 

Lynn

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It also appears that the signals differ in distortion levels.  Try the Harmonic Distortion Analyzer and SINAD VIs.  Lower THD values should be leading you to a better operating mechanical system.

LabVIEW 8.5.1 - 2019 Pro Dev
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Message 19 of 25
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Hi,

       I saw lot of threads on forum and I decided to use state machine with three states i.e.. Read from DAQ, set the stroke and ready to use. More, I have checked with all the pumps that are mostly same when they are working with noise i.e. the peak ranges are between + or - 0.7mV and if it gets noise the peaks are reaching + or - 3 volts.

      I am looking for exact option in labview that cn perform as, check the amplitude min and Max, if it over than + should ent or - 0.7mV , I want to enter into the second state to adjust with maximum value(let say 30) and if the peaks are in the range + or - 1.2v, I would like to adjust 10 more , if the level is just more that 0.7mV add +5 to serial device.

 

Is there any option available in labview.

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