Using ULx to connect to OMEGA DAQ-2416

[rhelling]

I am trying to use the ULx for NI Labview to pull data from a OMEGA DAQ-2416 board. I have installed the board successfully in InstaCal, and I am running TracerDAQ software and getting correct values for all of the thermocouples that I have connected. I worked through the example .vi pdf that and I have everything set up right that I can tell (http://www.mccdaq.com/PDFs/manuals/QS%20ULx%20for%20NI%20LabVIEW.pdf).

When I try to select the physical channels to select the board and the channel, I am unable to get anything in the drop down menu. I downloaded the latest ULx from the website (ftp://ftp.omega.com/public/DASGroup/products/OMB-DAQ-2416_OM-USB) under Labview drivers, and the board I have is here (http://www.omega.com/pptst/OMB-DAQ-2416.html). I have a request in to Measurement Computing to make sure the ULx and the DAQ-2416 are compatible, but I imagine they are since I got a link to the ULx from the DAQ-2416 page.

I am thinking InstaCal is putting the configuration file somewhere that Labview cant find it? But I am not sure where. The .vi that I looks the same as the on in the .vi example pdf in the first link. Not sure why I cant get it to work. I can get correct readings through some TracerDAQ software that I am using. Any insight is appreciated. 

[Bob_Schor]

There is some "magic", I think, about the InstaCal files.  My colleague has some of their devices, and I recall similar problems which were solved by "doing something I don't remember".  I'm currently several time zones away from him, but I sent him an e-mail asking for help, so either he'll answer you directly, or will send me the information and I'll post it here (assuming no-one else beats me to it).  This may, in fact, be a "solution to a different problem" (in which case I apologize for getting your hopes up) ...

Bob Schor

[Bob_Schor]

OK, so I "mis-remembered", but it still might be applicable.  Our case involved Vernier DAQ devices, some of which closely mimic NI devices (like the NI USB-6009).  Our case also involved getting code that worked in Development Mode to work in an Executable.

The trick was to explicitly put inside the LabVIEW Project the Vernier Library that was (in this case) located in a Vernier Folder inside LabVIEW's vi.lib Folder.  Here's what we did:

1. Create a Vernier "Virtual Folder" in Project.
2. Point it to the appropriate Data folder within the appropriate Vernier entry in the appropriate vi.lib folder in the appropriate LabVIEW folder in the appropriate NI Program folder.   [Sorry for all those "appropriates" -- it depends on your LabVIEW Version and "endian-ness", what Vernier tools you are using, and so on].
3. If you are Building an Executable, add the files in this Project Folder to the "Always Include" section of the Build.

For your situation, see if OMEGA put a ULx folder somewhere in vi.lib (or an OMEGA folder).  If so, see if the above steps (which are easily undone) help.

Bob Schor

[rhelling]

Thanks for all the info. I have a file: C:\Program Files\National Instruments\LabVIEW 2015\vi.lib\ULx that I believe you are referring to in your last line. 

Now I have a really basic question (I am getting back into LabView after years away...). I have just been creating .vi files to test out to see if I can pull data from the OMEGA DAQ devices.

I now created a project (instead of basic .vi), and I have a Labview project file. I created a virtual folder pointing to the ULx in the appropriate folder. Then I created a new .vi and copy pasted the code from my previous .vi attempt (the one that I cant get the drop down menu to populate). I still am unable to get the drop down menu to populate, i think i did what you described.

In my project in the dependency folder there is a thing that says the ULx_LB.dll has been deleted, renamed or moved on disk. I am wondering if this is my issue (see screen shot attached). But the reference to the ULx is shown in the silver folder above, so not sure what is missing?

[perhult]

I have used MCC units (the Omega DAQ-2416 seems to be a rebranded MCC unit), you should not need to mess with anything in your project. It should work out of the box by just using the ULx functions.

Don't you even see "Browse..." in the drop down?

Is your unit connected to the computer you are working on? Otherwise you are not going to see anything in the "browse window".

Can you attach the actual vi?

What happens if you simply type in the correct channel descriptor manually and run it?

I sometimes develop on a machine on which the MCC unit is not connected, then I simply type in the correct channels manually.

[rhelling · Accepted solution]

Ok so I called MCC and they told me what was going on. Apparantly when you set up this specific DAQ board you need to measure a voltage, and it will actually then output a temperature. You cannot set up the ULx Create Channel Sub-Vi for temperature, it needs to be set up for voltage. On top of this if you had previously configured this Sub-VI for temperature, the physical channel input remembers this regardless if you change it to voltage. You need to create a new .vi and bring in a new ULx Create Channel and set that up for voltage. 

If you go into this folder: ULx Create Channel C:\Program Files\National Instruments\Labview XXX\examples\ULx\Analog In you can use these already made .vi's to measure temperature, but choose the one that is for Analog Voltage. The one that you want to choose is circled in the attached screen shot. You will need to adjust the data rate etc to something that your board can handle, also beware of graph scaling.