USB 2408 not working in Dasylab in new installation

[Niels Skat Tiedje]

Hi,

I have been using a USB 2408 board with Dasylab 12 for several years without problems. Unfortunately, the computer I used died some time ago. I now have a new one with Windows 11 and then something has gone wrong.

Instacal finds the USB2408 easily if I use the latest version (the older versions do not seem to work).

When I test the module in Instacal, I get readings that are perfectly fine.

However, when I set up Dasylab to acquire data from the equipment, I get more or less random results. This happens both with single ended and differential setup.

I have a USB Temp module also. It works very well in the new setup, also in Dasylab.

Can you help me with this?

Best regards Niels

[DAQman]

Using DASYLab 12 on Windows 11 is unsupported. However, if the USB-TEMP returns good values, the USB-2408 should, too. Could you let me know what you're using for a signal input? It's probably a ground issue.

[Niels Skat Tiedje]

Thanks for the reply.

I use Dataforth double insulated thermocouple module they are in a rack with 6 channels. Each module gives a 0 to 5 V output.

I have not done any changes to the physical installation of the amplifiers and the USB2408. It is all mounted in a steel cabinet which is connected to the mains ground.

Was this the information you are asking for?

Best regards Niels

[DAQman]

InstaCal uses a lot of averaging when performing the analog loopback test. Besides setting the channel to single-ended mode, could you try using 60 for the data rate? This will act like averaging and providing smoother data. As always, you should close InstaCal before starting DASYLab. 

[Niels Skat Tiedje]

I just tried to set Instacal to 60 (Hz) and run in single endend mode.

While the reading in Instacal was very stable at about 0.6V which it should be for the temperature that the thermocouples are held at, then DasyLab gave very noisy results.

The noise is reduced, though and it is clear that changing the Instacal settings influence the results in Dasylab.

I set up two channels to measure temperature with a rate om 1Hz in Dasylab and then logged the results over some time. I plotted the data real time, but I also averaged them over 60 measurements.

The real time data shows noise on channel 0 varying about a slowly falling average. Channel 1 is constant at -9.35. The averaged data showed that the average slowly drops over about 8 minutes. I enclose a screen dump.

[DAQman]

Could you search your C drive for cbw32.dll and cb.cfg? Copies of these two files could explain the problem. For example, when you close the InstaCal program, it updates the following file with your settings: 'C:\ProgramData\Measurement Computing\DAQ\cb.cfg'. When DASYLab is started, it loads the DLL, which reads cb.cfg. So DASYLab is reading a cb.cfg file that InstaCal did not update and the inputs are stuck in differential mode. I'm hoping your search results in a single copy of each in the following locations:

C:\Program Files (x86)\Measurement Computing\DAQ\cbw32.dll

C:\ProgramData\Measurement Computing\DAQ\cb.cfg

Delete any duplicates.

 

 

 

[Niels Skat Tiedje]

Hi again,
I checked the files. There are no duplicates, and it seems that the cb.cfg file is updated by Instacal. At least the date is changed when I update in Instacal. I enclose a copy of the file.
The cbw32.dll is form May 25th last year. I guess that it is installed by instacal or the dasylab configurator.
I tried to install a USB 2416 4AO unit. I can measure temperatures very well with that, but voltage does not work in Dasylab.
It is quite confusing.

CB.CFG CB.CFG CB.CFG

Edited June 10 by JColvin
Added post on behalf of user

[DAQman]

Are you saying that even though you've configured some channels for voltage using InstaCal, the DASYLab Analog Input module says they are Temperature? 

The USB-2416 stores the channel configuration in non-volatile memory, which is updated once InstaCal is closed. If you leave InstaCal open on the desktop, it may explain why DASYLab isn't reflecting the changes. Also, the configuration is read once when DASYLab starts. If you need to make changes to InstaCal, shut down DASYLab, make your changes, shut down InstaCal, and start DASYLab.