In a browser session, components sometimes fail to load

This occurs when loading a session or when switching between tabs in a Tab component. Sometimes, the component eventually does load - sometimes it doesn’t and stays improperly loaded/invisible until the page is refreshed. This has happened maybe 10 times over hundreds of reloads.

Examples of problems:

  • An LED Display incorrectly shows a value of 0 despite the value of the bound tag, or shows nothing at all (this is the most common problem)
  • A Markdown component fails to load entirely and cannot be seen (also very common)
  • A Vessel or Label incorrectly shows a value of 0
  • An LED Display shows an incorrectly formatted number - for instance, “-14” when the format is set to #,##0.0 and it should be “-14.3”

A bit more information about the project:

  • Browser: latest version of Chrome
  • Ignition 8.1.7
  • Both the client and Gateway server are plenty powerful and have more than enough RAM (Ignition is using 2GB of the 16GB allocated to it)
  • A typical view has ~30 Markdown components, ~20 LED Displays, and a few other components
  • The project makes use of nested components for templating - for example, from top to bottom, Main View → Main Template → Unit Template → LED Display template → LED Display. Tag values are bound to parameters on the Main View and passed down.

This is much worse than I initially suspected. I switched a tab this morning on my test account and got an 'error writing to tag - insufficient write permissions" message. This implies to me the value of an Input component was erroneously loaded as 0, and Ignition then attempted to send this value to our PLC. This could be a huge problem in production.

I can only assume that the HMI is too heavy and complex for Ignition to handle, and I need to simplify some of the template nesting and bindings.

Write permissions doesnt sound like something going wrong with loading tho…
Did you check the security settings for the tags?

I don’t know what else it could be. There’s nothing going on with these Input values dynamically, just a bidirectional binding from the component to the template. I’ve gotten it to happen a few more times by rapidly switching tabs - it seems to be the same problem as when components are incorrectly displayed.

The security settings are properly set, this occurred on my test account (which shouldn’t be able to write values, and for which all inputs are disabled)

You might want to make a screen capture of the behaviour and send it to support (and here).

I’ll send it to support. Thank you.

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