Getting droputs on a 6PPT30.0702-20B connecting to a PLC; using web browser has no problems

We have an HMI which connects to a PLC. At various times, the HMI reboots by itself after losing connectivity. The message we get in the Logger (via a web browser) when these events happen is "Error executing action “clientSystem.Action.Navigate in context visualizationprototype000" and "clientSystem.Action.CloseDialog in context visualizationprototype010” but we aren’t touching the screen at the time.

Latest HMI version (1.6.2) is installed. When connecting via a web browser to the PLC, the response is far faster, BTW.

Hello Andrew,

Is the problem new or has it always been there?
Has the network cable to the PLC already been replaced?
Is the network cable connected directly to the PLC or via a switch or router?
Has the T30 been replaced before and the problem remains?
I suspect that the T30 is operating in VNC mode, please check the idle time of the B&R CPU. If the CPU usage is high, this behavior can also occur.

If you cannot solve the problem, please contact the B&R support in your area.

Viele Grüße

Dropouts were a consistent problem; we may have overloaded the HMI’s capability. Changing cables didn’t change anything; we do go through a switch. This has happened on multiple systems. Rewriting the HMI screens and spreading things out helped a bit. Running with a web browser had no problems, but it isn’t clear how you can check what the load is on the HMI or any HMI statistics. The PLC showed only about 40% load.

I will check if we are in VNC mode.

Hello Andrew,

the following information should only be taken into account if it’s a mappView visualization you’re displaying on the T30 panel.

Then the cause could be, like you already wrote, a overload of the HMI’s hardware possibilities (it sound a bit like that because you wrote it’s fine when you use the browser).

I would suggest to check first the performance guidelines to see how good these information matches with your visualization.

It’s worth a try to increase the watchdog value for the connection monitoring.

Best regards!

Just got something from B&R’s help line; worth sharing here-

We separate our widgets into classes to show which widgets can be run on certain panels. A T30 can run only A class widgets and graphing widgets are C class widgets. For example, LineChart, OnlineChart, OnlineChartHDA, and XYChart are all C class widgets, and we don’t guarantee that a T30 can run these. The T30 isn’t powerful enough for these graphing widgets. This is what is most likely causing the dropouts. If you wanted to run these graph widgets on a Power Panel T-Series, you would need a T80.