Computer Configuration > Policies > Centrify Settings > Mac OS X Settings > Security & Privacy > Log out after number of minutes of inactivity
Specify the number of minutes of inactivity to allow on a computer before automatically logging out the current user. The default value is 5 minutes.
Setting the value to less than 5 minutes disables automatic logout. If you plan to disable automatic logout, it is recommended that you set the value to 0 to preserve backward compatibility.
Note: Disabling this policy does not disable automatic logout.
This policy takes effect when users log out and log back in after the next group policy refresh.