I have an application where normally the screens are launched from a server, but I also have Panel Edition loaded on the local PC as a “backup”. If the server or connection to the server is down, the operator can launch the local client to control the machine. However, I want to “turn off” the tag updates from the local gateway when it is not being used to avoid unnecessary traffic to my PLC. I could use the Launch Gateway Control Utility and set the service to manual but there seems like there could be a better way. All my tags except for Alarm tags are leased mode, but they don’t seem to drop their subscription like they should. Also the alarm tags are in a direct scan class so those would keep updating all the time anyway.
First off, since you’re talking about the whole project being launched or not, I would expect the leased tags to unsubscribe. At any rate, in 7.2 the “leased tags” have been overhauled to work like virtually everyone expects- on a tag level, instead of a scan class level (in the current version, if even 1 tag in the scan class is in use- even in an expression, change event, etc.- all tags in the scan class are subscribed).
But I think there’s a hidden Panel edition feature request in there somewhere- when the “panel” is not running, don’t connect to devices. This would make a lot of sense, since a primary goal of panel edition is to work as a backup like you’ve described, and it’s not storing history or anything, so there’s really no reason for it to run when the panel isn’t up. I’ll talk to some people around the office and see what they think.