speed variation of an engine

[k.nadia]

Hi,

I have a signal PPP(point per point) of the speed of my engine  and I would like to calculate its variation continuously.

Is anyone has an idea ?

Thank you in advance

My best regards

Nadia

[EdgarShadyan89]

Hi. 

Can you share your VI`s.

Edgar Shadyan.

[GerdW]

Hi Nadia,

I would like to calculate its variation continuously.

Store the previous value in a shift register to be able to calc variations…

[Sam_Sharp]

You have not provided nearly enough information to be able to assist.

What sensors do you have? What is the range of the sensor? How do you convert the sensor value to engineering units? What DAQ hardware do you have? What data acquisition rate do you need? What do you want to do with the values after you have calculated them (throw them away? display them? log them to a file?) You should also post your VIs of what you have tried so far.

[k.nadia]

First, Thank you for response.

Sam_Sharp  I'm not using a sensor to get my speed I have a software installed in another computer and I'm using automation functions to get the value of the speed

I attached my VI if you could take a look

Thanks again

My best regards

Nadia

[GerdW]

Hi Nadia,

I'm not using a sensor to get my speed I have a software installed in another computer and I'm using automation functions to get the value of the speed

Ok, so you have a sensor and you get a reading with each iteration of your loop!

I'm not sure you need to open and close the automation refnum with each iteration…

Right now you calculate a speed variation, so what's your problem?

You might have a look at those Pt-By-Pt Statistics functions, they could help you to calculate mean and StDev…

[Paolo_P]

Hi Nadia,

Looking at this code it seems that you are already able to get that variation. If you want to store it they are lot of solution.

One of the simpliest is wiring that value into an auto indexed tunnel or initiate an array before the while loop and Replace the new values inside this array.

Notes :

1- You should avoid opening a connexion and closing this connection every while cycle. Put the Open Automation before the While to get the Refnum and close it after the execution of the While loop

2- Infinite While loop is never a good idea