RedundantDIObject Scan Group tab

Use the Scan Group tab to configure one or more scan groups. A scan group, or device group, contains items that will be polled according to a specified update interval.

The update interval for each scan group is inherited from the scan groups configured in the source DIObjects.

The item references for each attribute are not copied. Instead item references are resolved by the Primary and Backup DIObject data sources. If aliases are used, both source DIObjects must support the same set of alias names.

Note: You must configure at least one scan group before you can deploy the RedundantDIObject.

Click the Copy Common Scan Groups button to display the dialog box. This dialog box shows the scan groups configured in the Primary DIObject (shown in the Configured in primary window) and the Backup DIObject (shown in the Configured in backup window), and those scan groups shared by the two DIObjects (shown in the Identically named window). Click OK to add the scan groups in the Identically named window to the Available scan groups list on the Scan Group tab.

Important! Only scan groups shared by the Primary and Backup DIObjects should be configured in the RedundantDIObject. If you include non-shared groups, the RedundantDIObject will be placed in Warning state. If you configure non-shared groups in the RedundantDIObject first, you can add them to either DIObject source at a later time. You then must validate the RedundantDIObject to change it from Warning state to Good state. A special case is the unnamed Scan Group that is preconfigured in all DAS DIDevice Objects and in the InTouchProxy object. The unnamed Scan Group is represented in the RedundantDIObject editor as <Default>.

To configure additional scan groups, click the Add ("+" sign) button to start filling in a new group. To delete a row from a list, select the row and then click the Delete ("X" sign) button.

To add attributes to the Associated attributes list, select a scan group and click either the Copy Attributes from Primary or Copy Attributes from Backup button. All configured attributes from the respective DIObject sources (corresponding to the selected Scan Group) are added to the Associated attributes list (only attribute names).

To configure additional attributes for a scan group, use the Add ("+" sign) and Delete ("X" sign) buttons. The maximum number of attributes that can be preconfigured is 5,000 per Scan Group. You do not have to add attributes to a scan group; you can simply define the scan group and reference the device items directly from the client. Scan group attributes are simply named placeholders for values coming from the associated field device items. To reference attributes or items in a scan group that you create, you must include the scan group name in the reference.

Valid characters for scan group and attribute names include all alphabetic characters (A-Z, a-z), and/or numeric digits (0-9), and/or the following special characters: the underscore (_), the dollar sign ($), and the pound sign (#). Spaces are not allowed.

Runtime object attributes allow you to monitor scan group errors and other diagnostic information.

Options are as follows. For more information about the attribute associated with each option, see the attributes table in RedundantDIObject attributes.

Available scan groups:

This list contains all of the defined scan groups.

Scan Group (ScanGroupList attribute)

The list of names of all configured scan groups (special case is the unnamed Scan Group which is represented by a blank space). When a set is made with new values, it should contain a unique name for the scan group, from which data will be received. Group names should be unique across ScanGroupList, BlockReadList and BlockWriteList.

Ping Item (PingItems attribute)

The item quality of this item is checked on each scan to determine the Scan Group status.

Associated attributes for <scan group name>:

This list contains all of the attributes that are configured for the selected scan group.

Attribute (<Scan Group Name.>ItemList attribute)

The tag name of an item in the field device.