Global Variable List (Safety)
The Safety Global Variable List (GVL) serves the representation, declaration and editing of globally declared variables which are valid within the entire safety application. Multiple GVLs can be added to one safety application. The GVL contains variable declarations that can be used in safety extended programs (PROGRAM type POU) of the safety application. Function blocks (FBs) cannot access global variables.
A safety GVL is represented in the project tree by the 
symbol.
The global variables declared in the GVL object of the safety application are not valid project-wide, but only globally within the safety application.
Tip
For a better overview, you can create folders below the application in the project tree, and then add GVLs and POUs to these folders.
Select the SafetyApp safety application object in the project tree.
Select the context menu command Add Object with the selection Global Variable List (Safety).
Type in the name and optional comments for the GVL in the Add Global Variable List (Safety) dialog.
Click the Add button.
The GVL editor opens for declaring the global variables.
Select the GVL of the safety application object in the device tree.
Click Edit object in the context menu.
Open the cell to be changed by double-clicking it in the editor.
Change the contents of the cell.
Object Properties GVL
The properties dialog of a GVL contains the Common, Safety, and Access Control tabs.
Safety CRC
CRC of this GVL
Version (editable)
The developer can freely assign the version. The version can be used for quickly detecting the object version in the application list of the safety application object.
Comment: A comment for the GVL can be entered here.
For more information about the Common and Access Control tabs, see: Properties.