Publication 1756-PM004C-EN-P - October 2009 71
Data Access Control Chapter 4
External Access
Availability
The following table describes the conditions in which the External Access box
is disabled.
The External Access box is always disabled for any tag whose
data type is Alarm Analog or Alarm Digital. The external access
status is always Read/Write for these data types.
External Access Variables
Dialog Box/Window Considerations
New Tag The External Access box is disabled if:
• the tag is an alias tag.
• the controller is user locked online.
If you change the Type box from ‘Base’ to ‘Alias,’ the External
Access box becomes disabled and appears blank. If you choose a
target for an alias tag in the Alias For box, the External Access
box remains disabled and the external access value appears in
the External Access box.
The external access setting of an alias tag can only be changed
through its base tag.
Tag Properties The External Access box is disabled if:
• you do not have permission to change the external access
settings.
• the redundancy controller is in any state that does not allow
changes.
• the controller is user-locked online from another computer.
• the controller is safety-locked and the tag is a safety tag.
• the Scope is an equipment phase and the equipment phase
feature is not activated in the current license.
• the tag is an alias tag.
• the controller is in hard-run mode.
To Next Page
Loading...
Need help?
General
