Data connection over the internet

[fgc580]

I am using DAQFactory Express to collect data from a Labjack UE9 which is located at my remote cabin. I can connect to the device fine using the Labjack LJControlPanel utility, and sometimes with DAQFactory, but the connection gets broken after a few minutes (or seconds) and once the connection breaks, DAQFactory does not recover. I have to kill the program via task manager and restart to reestablish the connection. I expect the problem has to do with the latency of the internet connection. Is there some more robust way to make this connection? Can I control how long the software waits for a response, or some more graceful way of handling the UE9? The LJControlPanel utility has never lost the connection, but it has very limited functionality. Thanks,

Jeff

fgc580@comcast.net

[AzeoTech]

You'll actually have to ask the LabJack folks why the UD library functions don't maintain the connection, but the ControlPanel utility does. The DAQFactory LabJack driver simply wraps the UD and lets the UD handle most everything. This makes it so LabJack can release new devices and features which you can take advantage of without us having to release a new DAQFactory.

You might try connecting to the UE9 using Modbus and a standard DAQFactory Ethernet connection instead. Then you aren't relying on the LabJack driver software, and you'll have a fair bit more control. The only thing is that you won't be able to stream.

[LabJackSupport]

Perhaps there is something different about the behavior of LJCP versus DF when the connection is lost. Perhaps LJCP does something to recover that DF is not doing? How often does the problem occur? If you could use Wireshark to get a capture of the traffic in both cases we could look at that capture.

[AzeoTech]

As I said, DF doesn't establish the connection to a LabJack, nor maintain it. It is all handled by the LabJack UD. I don't know if the LJCP uses the UD as well.

[fgc580]

Regarding how often the problem occurs: This happens every time I run DAQFactory, it is just a matter of how long the connection lasts. My best case was almost 3 hours without an error. The worst case is on the order of seconds. The most common case is 10-15 seconds.

If I were to capture using wireshark, I would rather not post the file to the forum, for security reasons. Is there an email address I could send it to?

[AzeoTech]

As I said before, you should contact LabJack about this as the problem is almost certainly in the UD. I don't have access to the source of the UD so can't address any problems that might lie there in. Email them the wireshark info at their support@ email address.