The Core Tag serves as a common base for all other types of Tag.
The configuration properties of the Core Tag relate to its identification and its user rights:
| Property | Type | Version | Description |
|---|---|---|---|
| DriverName | WSTRING | 1.0 | The name of the driver providing this tag. |
| Name | WSTRING | 1.0 | The name of the tag within its folder. |
| ParentFolder | WSTRING | 3.74 | The name of the folder that holds this tag. |
| TypeLabel | WSTRING | 1.0 | A short description of the tag type. |
| TypeName | WSTRING | 1.0 | The tag type name. |
| Description | WSTRING | 1.0 | A description field where you can enter a description about the tag. |
| UserField1 | WSTRING | 1.0 | A field where you can store application specific data. |
| UserField2 | WSTRING | 1.0 | A field where you can store application specific data. |
| EventSeverity | UINT | 1.7 | The severity of Event Log entries for state changes associated with this tag. A value of zero disables storage of state change events. |
| EventSeverityConfiguration | UINT | 3.25 | The severity of Event Log entries for configuration changes associated with this tag. A value of zero disables storage of configuration change events. |
| EventSeverityOperator | UINT | 3.25 | The severity of Event Log entries for operator actions associated with this tag. A value of zero disables storage of operator action events. |
| UserPrivileges | DWORD | 3.93 | The privileges available to the current user for this tag. |
| UserRightsZone | USINT | 1.5 | The security zone for the tag |
The UserPrivileges property is a bitmask of the privileges the user has for the tag.
| Bit | Mask | Name | Description |
|---|---|---|---|
| 0 | 16#1 | Refresh | The user can request a data refresh. |
| 1 | 16#2 | Write | The user can write to a data point tag. |
| 2 | 16#4 | Force | The user force the value of a data point tag. |
| 3 | 16#8 | Acknowledge | The user can acknowledge alarms. |
| 4 | 16#10 | DisableAlarms | The user can disable and enable alarms. |
| 5 | 16#20 | DirectWrite | The user can directly write to a device. |
| 6 | 16#40 | WriteFile | The user can write a file to a device. |
| 8 | 16#100 | Configure | The user can configure the tag. |
In an Operator Action, use this type of IF statement to check if a user has a certain privilege:
(* Check whether the user can write to the device... *)
IF (%"TagName.UserPrivileges" AND 16#2) <> 0 THEN
(* The user can write to the device *)
....
END_IF
For more information see User Rights and Privileges.
The UserRightsZone property together with the User Rights define what each user can do with each tag. The UserRightsZone defines which security zone the tag belongs to. To change the rights assigned to users:
The Core Tag supports these data properties:
| Property | Type | Description |
|---|---|---|
| Quality | INT | The quality of the data of this tag. |
| Timestamp | DATE_AND_TIME | The timestamp of the last update to the data of this tag. |
The Core Tag is used as a building block for these tag types:
For the meaning of terms used in Fernhill SCADA.