Possible Breaking change between 7.9.13 & 8.1.35

Ignition
,
1

I have the need to include the OPCItemPath in a Transaction group in Vision. Previously (Ignition 7.9.13) we had this working by adding an expression item to a tag within the same group with this syntax:
{[~]IN_Code_0.OPCItemPath}
however since upgrading to 8.1.35 this no longer returns the tag opc item path but instead returns the current value of the referenced tag.

What is the correct syntax to get this path? I have some 90 or so groups configured this way and this has broken the recording in the Project :frowning:

2

Try changing ~ to default or the name of tour tag provider.

3

That doesn't fix it (the tags are from the same group, hence the [~] reference)
I also tried using the full tag path with the [default]path-to-tag-in-question.OPCTagPath and it too just returns the value of the referenced tag.

4

Here is the path to the current docs for tag properties:
https://docs.inductiveautomation.com/display/DOC81/Tag+Properties

Perhaps the property you need can be found in there.

5

Hi, I did look through there before posting. even thought it may be a case sensitive change, as my original working code had OPCItemPath and I noticed that was opcItemPath, but no difference.

6

As a work around I have converted every one of those expression tags to "memory" tags & copied the relevant OPC tag Path to the value... This saves my bacon for now, but I would really like to know how I should set those up for future groups.

7

Make sure that your tag's Data Type is String, and the Current Foldder is '[.]', and the path property name is OpcItemPath.

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8

Thanks, but that looks to be in some other area than a Stored Procedure Transaction Group within Vision?
I have the group set up like this (which worked perfectly for Ignition 7.9.13)
image

where the Item Named "StatusOut" references an OPC Tag:
image

and the expression tag is set as:
image

(Which as mentioned, worked flawlessly in 7.9.13)

In 8.1.35 this expression tag simply follows the value from the tag itself and doesn't return the Opc Item Path as expected.

9

You need to contact support. This could very well be a legitimate bug, but support is your best avenue to figure out whether it is or not.

10

Thanks, I will do. Just wanted to be sure I wasn't the cause first.

11

Hi Paul,
I ended up lodging a ticket which has been confirmed as a "bug" and the behaviour is replicable between 7.9.21 and 8.1.35 by Lucille. I've since confirmed that it is still there in 8.1.36.
My workaround of changing the TagPath Expression tag to a memory tag & manually adding the actual opcItemPath value for each transaction group has worked for the interim. So now we wait until the fix comes through.

Thanks one and all.

Regards,
Peter.

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