Hi,
This is a legit error, but I am searching for a way of handling this error in a custom way -not having Ignition bring up this default Error message.
-Is it possible?
This example is when using system.tag.write()
How are you trying to write to the tag, a binding or a script? (Or other I suppose.)
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You would use a try: … except: block in python.
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For info: In this example I am writing to an OPC tag with bad quality.
-Actually I was manipulating the tag from within a template. Writing to the UDT property representing the tag. My first post was not accurate…
When switching to system.tag.writeAsync() or -Blocking() functions the Error message does not show in the client. I will consider using this approach instead
I get the same error message appearing when manipulating a bad-quality OPC tag directly in Designer/TagBrowser - which is perfectly fine.
I was just wondering since some earlier posts mentioned an additional argument for the tag.write function for suppressing errors…
case closed ;-).
You were writing through a binding, even though in a script. Bindings display their own error messages because they are often triggered directly by UI operations.
I see. Would there be a best practice to handle / catch an error when writing through a binding?
There’s not really anything you can do after the fact. A binding can’t let an exception pass through to a calling script because there may not be a calling script, and there’s no practical way for a binding to know. You’ll need to check the quality of the tag before attempting to write to the bound property.
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