Symbol: 
Function: This command logs out the user currently logged in to the controller (device). If CODESYS still has a connection to the controller, then it will be disconnected.
Call: Main menu “Online”.
Requirement: The application is in online mode.
You can manage the device user management in the “Users and Groups” tab and “Access control” of the device editor. The commands in the “Online Security” menu provide another simple option for protecting access to the target device.