Define which Property Values Derive from a Group Template

Configuration that does not vary in the Group Instances that reference a Group Template need be specified only once—in the Group Template. You use the Template’s Property Overrides feature to specify which configuration is derived automatically from the Group Template, and which configuration needs to be modified directly on a per instance basis or calculated from a parameter set in the instance using expressions defined in the Group Template.

To use the Property Overrides feature to specify which property values derive from a Group Template:

1. Display the Database Bar (see Display an Explorer Bar).
2. Configure the Items in the Group Template.

   (The properties are that are included in the Property Overrides window will vary, depending on the items’ configuration.)

3. Right-click on the relevant Group Template in the Database Bar.
   A context sensitive menu is displayed.
4. Select the Edit Property Overrides option.
   The Property Overrides window is displayed. It contains a tree-structure that, at the top level, consists of the items in the Group Template, and a set of default overrides for the Template itself.

   The window displays the configurable properties of the Group Template and the database items that have been added to that Group Template.

   

   To display the configurable properties for an item expand the branch of the item.
   The tree-structure expands to display the properties of the item you have selected.

   

   For further information about configuring a property's value using an expression, see Use Template Expressions to Configure Property Values, and see Configure Template Parameters for use in Template Expressions.

   You can add or remove properties from the Property Overrides window by using the Select button, which displays the Select Properties window.

   

5. Expand the branch of the item for which you want to change or check the configuration (see Understanding the Select Properties Window).
   

   Remove a property

   You can remove a property from the list in the Property Override window.
   The value of a removed property is inherited from the Group Template (as opposed to being configurable on a per Group Instance basis).

   

6. Select the OK button when you have completed any changes in the Select Properties window.
   The Select Property window is closed.

You will now be able to configure the values of the selected properties, either directly in each Group Instance that references the Template or by using Template parameters and Template expressions defined in the Group Template.

Further Information

Configure the Properties that are Unique to the Items in a Group Instance (the configurable properties are those that are included in the Property Overrides window).

Examples that further demonstrate how the Property Overrides feature might be used on a Geo SCADA Expert system: see Example Configuration.