12-03-2014 04:26 PM - edited 12-03-2014 04:41 PM
I'm trying to acquire data from my 34460A using IVI. When I use Configure Measurement, the DMM doesn't seem to be taking the resolution properly. It seems to be setting full range (slow) measurements no matter what I set there. I set the range to 3A and the resolution to 0.0001 but I'm getting measurements in the 4±2µA range
http://sine.ni.com/apps/utf8/niid_web_display.model_page?p_model_id=21588
FYI, the non IVI (LabVIEW) driver works fine.
12-04-2014 11:18 AM
Hello Oligarlicky,
So devices that are IVI compliant are usually advertised as such. Unfortunately, I was unable to find any information or verbiage from the manufacturer's website that indicated the 34460A is in fact IVI compliant. Here's the link for the product page: http://www.keysight.com/en/pd-2269458-pn-34460A/digital-multimeter-6-digit-basic-truevolt-dmm?cc=US&...
Additionally, it seems on the link you provided for the drivers, under the IVI drivers, it lists the models that have been tested with the IVI drivers. It turns out that the model in question, 34460A, has its tested status listed as "Blank". See attached photo:
From what I've gathered, it seems that the 34460A is most likely not compatible with IVI drivers. At least the LabVIEW Plug and Play drivers work. Was there any reason you wanted to use the IVI drivers over the LabVIEW Plug and Play drivers?
Regards,
Jae
12-04-2014 11:23 AM
Yes, I wanted to use the IVI drivers so I could drop this instrument into an existing software deployment that uses IVI or at least drop it in with as few changes as possible. The two intruments (34460A and 34461A) are so similiar that I suspect you'd find the same issue with the 34461A though I don't have one available for testing.
12-04-2014 11:36 AM
12-04-2014 08:25 PM
Would you please use I/O Trace to record the commands sent to 34460A by LabVIEW PnP and IVI-C respectively? We’ll probably find the cause of the issue by comparing the command logs.
I noticed that in LabVIEW PnP, it will send ***:RANG:AUTO OFF before setting the range and resolution. However, in IVI-C, it sets the range and resolution directly without sending ***:RANGE:AUTO OFF.
Generally, range auto feature will be automatically turned off after setting the range and this is why IVI-C skips sending ***:RANGE:AUTO OFF. However, you can try to add code to IVI-C driver to send ***:RANGE:AUTO OFF command explicitly and see if this solves the problem.
Take DC_VOLTS_RATIO measurement function for example, in function ag3446xAttrRange_WriteCallback, add one line before setting the range (see the attached snapshot).
12-05-2014 11:21 AM
Where is that file located?
12-07-2014 06:10 PM
If you install the IVI-C driver by it's default location, you can find the source files at:
C:\Program Files (x86)\IVI Foundation\IVI\Drivers\ag3446x, C:\Program Files (x86)\IVI Foundation\IVI\Include\ag3446x.h for x86;
and C:\Program Files\IVI Foundation\IVI\Drivers\ag3446x, C:\Program Files\IVI Foundation\IVI\Include\ag3446x.h for x64.
By the way, after modifying the source code, you need to replace the ag3446x_32.dll/ag3446x_64.dll to make it work.