Scan class problem

I started having problem with scan classes and couldn’t identify the cause.
In Gateway Console I get such error:
(id=7731bc61) No scan class information found for tags. All returned data will be bad quality.

How to identify the cause of this error?

What version of Ignition are you using? You probably need to upgrade to the most recent release.


That error is unfortunately unnecessarily misleading. It usually means that you are querying tag history for tags that have no history available (in other words, you are querying tags that don’t have history turned on).

This commonly happens when trying to use indirect history bindings. It could also happen by simply defining tag history pens for the wrong path.

Finally, it could be caused by some sort of issue with the database, where tag history data hasn’t been stored successfully yet. Check the Store and Forward system status page (in the Gateway, under Status) and see if anything is reported as quarantined, or if the data is backed up.

Let us know how it goes,

Thank you!
Turned out, one tag path was invalid and easychart tried to fill it’s dataset with wrong tag path.