A Viewer Only mode (Read-Only or restricted access mode) is a way of controlling access from an E3 Viewer to a server (Domain), as opposed to a Viewer Control mode, which has no access restrictions.

By using user permissions settings (on chapter Security), and according to the type of E3 Viewer license in use (on chapter Domains), a server then determines whether an E3 Viewer is in Control (normal) or Only (restricted) mode. When an Only mode is on, several restrictions apply to actions that can be written to a server. In this case, the following items are blocked (by a script error or by generating an error message):

•General writing on server's object properties via E3 Viewer Links

•General writing on server's object properties via E3 Viewer scripts

•Viewer's SetValue and ToggleValue methods (including Load and Toggle Value Picks)

•Calling server's object methods via E3 Viewer scripts (please check for exceptions further on this topic)

•User administration via E3 Viewer (by using Viewer's UserAdministration method)

•Acknowledging alarms via E3Alarm

•Using Viewer's LoadFormulaDlg, LoadFormulaValues, and LoadFormulaValuesQuiet methods

The following items remain allowed when this mode is on:

•Reading server's object properties, via Links or scripts

•Calling methods considered non-restricted for server objects via E3 Viewer scripts:

•Item (all objects)

•Refresh (OPC Group)

•FindUnit, FindValue, GetValueData, and GetUnitData (Formula)

•GetAlarm (Alarm Source)

•GetE3QueryFields, GetADORecordset, and GetAsyncADORecordSet (Query)

•GetObject (ServerApplication)

•Changes in the Advise status of server Tags

•Changing user's own password (Viewer's ChangePassword method)