Global tags in FSQL?

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1

I will attempt to describe what I would like then you can tell me if there is such an item in FSQL.

I want to have a folder called timeset. In that folder there will be a group that gets the current time and date information from the SQL server. There will also be a conditional clause that when the time is equal to a certain time it will set this bit. Now this part I have working.

What I would like from this point is several folders that connect to the settime of the PLC’s. This I have also been able to do. However I dont want any of the data to go thru the SQL tables. Again using Colbys suggestion of the ctrl-space I am able to accomplish this. What I can not do is get this trigger from the SQLTIME group to trigger the rest of these groups so that they will also set the time.

Can you have more than one write back to field with the { }?
Example Write data to {1}, {2}, {3}, etc…
And if this is possible how many can you have in there at one time?

Or is there a global tag I can set in one group and read in another group without having to go thru the SQL database/table?

2

If you don’t want an FSQL item to be stored in the SQL database, double click it and select read only.

The easiest way to trigger several groups is to use the same OPC tag as the trigger in each group. It’s OK to set that to “read only” if you want. Alternatively, you could use a value in the SQL database for this purpose.

I’m still getting the feeling from your posts that you’re paranoid to use the database based on the SQL Server transaction log. It’s no big deal. Set the database up to NOT LOG and you won’t need to worry about it.

To answer your question, there is no “global tag”, but you get exactly the same effect by using one PLC tag in many groups.