LabVIEW
statistics
I have a NI cDAQ that couldn't read a counter signal and analogic signals at the same type
So my problem is i need adquire 1 counter signal and severeal analogic signals ( current and voltage) and make statistics of 300 measures with the frequency of 10hz (0.1seconds), i can not wait 30sec to read this 2 different signal i use to diferents cdaq assistant but i don't know how i may do the conections with de statistics
Hi Imrmendes,
but i don't know how i may do the conections with de statistics
You have to draw wires from the data output of the DAQ assistent to the Signals input of the Statistics ExpressVI...
Quite easy 😄
Hi lmrmendes,
when you don't know all these things you definitely should start with some LabVIEW101 as provided here or here or here.
When you have gone through all that lessons you should open the example finder found in the help menu of LabVIEW to look for suitable example VIs.
Then you should know how to
- setup ExpressVIs
- use a loop for repeated processes
- avoid ExpressVIs for better programs...
i had try this 3 way's
in this way my result is 1
and the next 2 way's the 1st doesn't work and the 2sd never stop
@lmrmendes wrote:
So my problem is i need adquire 1 counter signal and severeal analogic signals ( current and voltage) and make statistics of 300 measures with the frequency of 10hz (0.1seconds), i can not wait 30sec to read this 2 different signal i use to diferents cdaq assistant but i don't know how i may do the conections with de statistics
Why can't you wait the 30 seconds for your data? If you don't have your data, you can't do your analysis.
Why are you passing the array size into your anlaysis VI? That isn't useful for you. You need to pass the actual signal out.
Take a look at the tutorials GerdW recommended. They should help you out. In all three cases you are only going to get a the last value out of the loop. I know this by looking at the tunnel coming out of the loop (the little square solid box your wire is attached to). If you want to get all your samples you will need to build it into an array. There are lots of ways to do this but the easiest is to enable auto indexing. This will create an array of all the values out of the loop. You can do this by right clicking the tunnel and selecting "enable indexing". It will change the way it looks as well. In the image below the top tunnel has auto indexing enabled and the bottom does not so you can see the difference.
That being said I don't know that you actually need to use a loop. If you know how many samples you need to take (and it sounds like you do) you can simply set the DAQ Assistant to acquire N samples. When this is done it will just take N number of samples and then stop and output the data. You can wire this to the Statistics VI.
When you use express VIs you can not see what they are doing. This is one of many reasons they are not frequently used by the more experienced LabVIEW programmers. For that reason it is pretty difficult for us to know what else you might be doing incorrectly. If you need more help we will need more detailed explanation of what you are doing and what you want to do. You can even post your code if you would like.
Good Luck!
the ideal was adquire the signal at the same time that's why i cann't adquire 30 sec and then adquire another signal
at the momento 1 of my problems is resolve in the frequency i can take the mean of a interval by this way
at my second daq assistant i have 7 signals i need to make the same that i had done on the frist and make a timed loop that runs in 10hz but with this configuration is still running one cycle per second
