At redundancy switch of zenon servers, a variable with "alternative value" (ALT_VAL) suddenly gets the INVALID bit added - breaking ALC

At redundancy switch of zenon servers, a variable with "alternative value" (ALT_VAL) suddenly gets the INVALID bit added - breaking ALC

Description

When a variable with INVALID status gets switched to "alternative value" some drivers on the active server add status ALT_VAL and remove status INVALID for this variable.
After the standby server takes over the active role (redundancy switch), the drivers use both, INVALID and ALT_VAL, status for this variable.
This caused the Automatic Line Coloring (ALC) status to change from a defined state into the undefined or error state.
The ALC has been updated to allow for INVALID AND ALT_VAL status as defined state. The ALC status no longer changes to undefined after a redundancy switch.

To benefit from this fix: 
  • Update your zenon Software Platform to the latest build of zenon 11 or higher. 



Item ID: 291095
Version: 14.00 Build: 358890
Version: 12.00 Build: 365438

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