Measure with manometer and control valves

[Vanrob]

Hello everybody,

I am a industrial engineer ind biochemistry and I will use LabView. I have only basic knowledge about it.

The materials is not still arrive but here it is: 

NI cDAQ-9174: https://www.ni.com/en-us/shop/model/cdaq-9174.html
NI 9203: https://www.ni.com/en-us/shop/model/ni-9203.html
NI 9472: https://www.ni.com/en-us/shop/model/ni-9472.html

I would like measure a pressure with a manometer. Open valves, measure the pressure, arrive at the pressure we want, close the valve and after open/close others valves.

So, I would like to know if there is examples for this kind of use in the LabView data ?

As I am a beginer, it will be easier than if I trying to make something alone.

And, by the way, is it possible to generate an output for valves and input for manometer ? As I do not have already recieved the cDAQ, I cannot have the signal but I would like start the programm as soon as possible because I already see a lot work on it.

Many thanks for your answers.

Bests,

Vanrob

[hecmar.arreola]

You should be able to accomplish this in LabVIEW.  The measurement side of things should be fairly straight forward, but the control side could be a bit of a learning curve for you depending on what your programming background is.

I would recommend the following steps to solve your problem:

* Draw a flow-chart of your proposed solution as you have described it.  This will help you when you get to programming your solution.

* You can use a simulated DAQmx NI cDAQ-9174 to get you started.  Goto Measurement & Automation Explorer->Devices and Interfaces->right-click "NI-DAQmx Devices"->Create New..->Simulated Device

*Go through all the LabVIEW tutorials on the NI website.  These will get you familiar with LabVIEW.

Beyond that, it is difficult to help you without posting an out-right solution to your problem.  If that is what you are looking for, I'm sure there are a number of good folks that hang out in these forums willing to consult with you on a solution ;).

Your problem is easily solved by LabVIEW, so you are on the right course. 

[Vanrob]

Thanks for the information Nickerbocker.

I tryied to do something. I supposed the manometer was connected and I tried to read the data generate from it and open a valve when the vacuum is good enough.

Can anyone tell me if this look right for the moment ? (I work with LabView 8.2)

If you have any advice...

[Vanrob]

Or maybe should I try on this way, with the help of DAQmx ?

One of my teacher just show me quickly like I do in the first enclosed. But I saw on litterature, they seems to do that with help of DAQmx and configure the style of work they do.

It seems similar but there is some difference.

Which way is suppose to be the best ?

Thanks,

Vanrob

[Vanrob]

Hello,

With more information about that, we told me functiuns was better than assistants as DAQmx.

I try different things and finally arrive at the enclose vi.  We finally receive de last pieces of our module and I can try it.  It seems as if it receive datas from the manometer, can send in the digital output module and I have no errors when I lunch/end the vi but there is nothing on the graphical indicator.

How LabView recognize the 4-20mA received to put it in another unity (bar, mmHg,...) ?  Or how are we suppose to do the "translation" ?

It is maybe the problem on this graphic because a Waveform chart seems make a line for the graphic but it is not in the unity of the manometer but in mA (I think)

Yours Sincerely,

Vanrob

Message Edité par Vanrob le 04-10-2010 10:33 AM

[Vanrob]

Hello,

Here is the evolution of the work: If I change my Waveform Graphs by a Waveform Charts, the problem is solved.

For the "translation", I suppose I need to see that with the manufacturer.  They must have a "simple" multiplication to do before my Waveform Charts to have the mA in bar, mmHg, Pa,...

Yours Sincerely,

Vanrob