Using Two DAQ, is it possible?

[carlosdga]

Hi you guys! First of all, my name is Carlos and i´m a student of Mechanical Engineering. At the time, we dispose (in our university) from several test banks that are in poor conditions, so I been told to repair one of them. In`s a Refrigeration Test Bank (I attached a photo), it´s out of any operation so I have to put it operative again at first, then I have to replace all the analog indicators you see at the photo and become them digital. I`ve been doing some research on the web and I found the NI-6008 (This DAQ has been used in several applications in the University), I saw it can be connected with the LABVIEW SignalExpress, and it´d would be easy (in a manner of speak) in my case because all I have to do is display and register the values (temperature and pressure) from the bank and the program allows me that.

The problem surges when I see that NI-USB 6008 has 8 Analog Inputs, and I need 10 AI, so I´d have to buy two of them (Because is the cheapest one and I don´t have too much money) and I would like to know if there is any problem about connecting both DAQ at the same time? Is it possible to connect them with the Labview SignalExpress?

I hope to get some replies so I can solve my problem. Thanks for your help

Best regards

[DFGray]

You can certainly use two 6008s at once.  And SignalExpress will handle them, as well.  If you have no programming experience, SignalExpress can get you started.  If you want specialized analysis or display, you can use SignalExpress to generate code to LabVIEW to get you started on an application.  Note that this code will be the data acquisition and analysis part of your code.  You will still need to write the GUI properly using event structures.  If you do this, post on these forums for some tips to get you going in the right direction (e.g. use producer/consumer and state machine architectures).

[carlosdga]

Thanks a lot for your help DFGray, you just have gave me a valuable info.

If I can use both DAQ at the same time, NI USB-6008 is my solution. I won´t hesitate to ask for your valuable help in case I get stuck somewhere in the project

Thanks a lot

Best regards

[carlosdga]

I´m sorry for making this, I guess this is not allowed in the forum, but it´s a question that I made myself a few ago while i was checking the LABVIEW Signal Express.

I have to measure pressure, and I noticed Signal Express doesn´t offer the Pressure option. I know I need Pressure transducers so I can turn pressure into current, which will be measured and registered in the program. But i need to display the Pressure value on the screen and I was wondering if it´s possible to do that with Signal Express,

Thanks and best regards   

[NIquist]

It's often dificult to get help regarding "Express" fuctions since most of the advanced forumites don't use them.  I don't know if you can set up scaling with SE like you can with LabVIEW and MAX but I suspect you can.  In any case, it sounds like you might want to use LabVIEW for this project if you have the choice.  The time you spend on the learning curve will be well worth it if you want to use LabVIEW for more advanced projects later.

EDIT:  Just checked.  The Full Version (not LE) of Signal Express can indeed do scaling and conversion so you should be able to scale your voltage input to a pressure value before displaying/logging.

[carlosdga]

Thanks for time taken to share you opinion.

I certainly would like to use LABVIEW for this Project. But I´ve seen Signal Express fits perfectly for my problem and it´s aparently easy to work with. I hope I  have the chance to go deeper into the Labview world because i´ve reading about it and it looks fascinating.

When you say Signal Express LE, you mean Limited Edition right? I downloaded it yesterday in order to try it and see how it works, but I don´t have the DAQ´s yet so I can really see how it works.

[NIquist]

Yes, LE is the free, limited version.  You will have 30 days to try the full Signal Express features.  Then it will revert to LE only and you lose all the full version features.

[carlosdga]

I´m going to get the full version then. By the way, you know which are the DAQ that are compatible with Signal Express? I´ve read there are many, but I can´t find any of them

[NIquist]

I really don't use Signal Express but I think you can use most multi-function DAQ cards with it (although I don't know if you can do simultaneous sampling). 

Do your research before you buy anything.  SE FULL is $750, LabVIEW (base) is $1250.  Signal Express may be easier for simple tasks but compared to LabVIEW it's kind of a joke.  SE is really just a glorified data-logger bundled with some analysis functions.  LabVIEW is an actual programming language.

[F._Schubert]

But the data analysis in LV is part of the FDS...no, don't use the base at all means, not even events there... well, univercity you said? propably a student license will be enough, otherwise check if you already have a campus volume license.

Felix