how to measure the inductance with a ELVS board

[jingrui]

Hi, Hani

Thanks for your patience again. I've found one example named "DMM Basic" in the ELVIS folders and I make some change so as to measure and read the inductance, and I inserted my magnetic system into the ELVIS board in Current Hi and Current low, then I connected the Current HI with ACH1+, the Current Low with ACH1- with two wires. Then I selected 'dev1' as device name, but the VI occured some error and popped out a warning window which says  "ERROR 9320 occured at NI ELVIS DMM-close vi' and it also gave the possible reason ' The specified refnum type is invalid. For instance, you may have connected a refnum from a FGEN VI to a variable power supply VI.'  So I guess maybe I chose a wrong device name.

So can you tell me why the software can not work and how should I choose the device name.  I will try to program as what you suggest tonight to see if it can work.

Looking forward to your reply. Thanks

Jingrui

[Hani R]

Hi Jingrui,

The following KnowledgeBase article describes the error you are getting: KB 3G8AEEBJ: Why do I get Error 9320 When Running a VI With NI ELVIS.  It sounds like you have selected the incorrect device.  To use NI ELVIS you need to have it connected to a DAQ card installed in your computer. 

When the DAQ drivers were installed, a program called Measurement and Automation Explorer (also known as MAX) should have installed with it.  When you open the program, expand the Devices and Interfaces tab.  If you have a DAQ card, you will find it under NI-DAQmx Devices with the device number listed next to the device.  Perform a search on National Instruments' website if you are not sure what the type of hardware the product name corresponds to.

[jingrui]

Hi Hani

Sorry to respond you two days late. And I've got my program work now. I just used the example VI, Basic DMM VI, given by the ELVIS and modified it to what I want as you told me, and fortunately I figured out the reason why it gave me the error warning.   With the program I am done with my project.

I'd like to post my block diagram here, but I can not post it here by using the 'insert a image' command of this forum.

And I would like to show my gratitude to you here, without your help, I would never stand a change of getting it done, I really appreciate it! Since I am studying how to program in Labview now, I am sure I will have a lot questions to ask you in the near future. ^_^

Thanks again and ll the best to you!

Jingrui