Wonderware syntax for nested UDTs

Normally when I add a controller scoped UDT the tag is entered in the item as is...

Tank_A.Level_Sp

Since I’m programming 15 or so tanks with similar instruments I nested a few UDTs. Now the syntax looks like this..

Tank_A.Level.Sp
Tank_A.Level.Actual

Values weren’t updating once I went to runtime. I checked the system management console log and noticed all the nested UDT tags are invalid.

I’m hoping someone has been through this before. I’m going to dig through the user guide once I get home.

Your syntax looks correct. I vaguely remember seeing a bug fix for the AB OI server a little while back for not updating tag database correctly. I think there's an option in SMC to update controller tags manually. Otherwise try stopping and starting the driver.

Saffa said:

Your syntax looks correct. I vaguely remember seeing a bug fix for the AB OI server a little while back for not updating tag database correctly. I think there's an option in SMC to update controller tags manually. Otherwise try stopping and starting the driver.

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Resetting the driver solved my issues. It was strange because my other tags were updating, just not the nested UDTs.. that’s what lead me to second guess the syntax.

Stopped and starter the server and everything was back to normal.

The driver maintains a list of tags within the controller. It's supposed to update this when there's a change but it doesn't always work especially with older versions.

Restarting the driver causes it to fetch the list again from the controller.

I'm thinking the method to manually update the list might be via a built in driver $tag. Its been a few years since i last worked with an AB PLC and wonderware, Maybe someone Wilde knows specifics.

I think the tag you are referring to is to invoke a 1 into "Galaxy:'YOUR_COM_OBJECT_HERE'.'YOUR_TOPIC_HERE'.$Sys$UpdateTagInfo".

DASABCIP has had many hot fixes for the various versions over the years. Your best bet is to work with WW for any hot fix you may need for your version.

In larger systems, the use of the "Auto Synchronize Tags" setting in DAS can have performance issues if the tag counts for that PLC are high. You may find to have better performance if you leave this setting off, however the trade off is that every time you add a new tag to the PLC, you must stop and restart the driver to pick up the new tags. You can try to invoke the tag mentioned above through your object browser or Intouch screens, but I've seen that not always pick up new tags. Stopping and restarting the driver insures the tag list gets rebuilt from scratch. Again this may just be a hot fix issue however. I have seen large systems take 3 minutes or so to build the tag list.