Data Management Capabilities > Managing Part Structures > Part Structure Browser > Part Structure Information > Attributes Tab > Occurrences Tab
  
Occurrences Tab
An occurrence in Windchill is a database object that stores information about one named usage of a part within a part structure. The name of an occurrence is called a reference designator. For example, the top assembly of an automobile must have a quantity of 4 tires. Each use of the part “tire” in the automobile assembly can be assigned a reference designator such as T1, T2, T3, and T4 and can contain unique information such as the geometric positioning of the tire image within the image of the automobile assembly.
You can see each individual occurrence of a part in the Structure tab on a part information page by highlighting an assembly part in the structure pane and selecting the Occurrences tab. There will be a row for each occurrence for all parts used by the assembly.
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Each part usage relationship has the potential for a number of occurrences equal to the quantity. However, occurrences are only created when occurrence specific information, such as the reference designator, is added.
For example, a part may be used 6 times in an assembly but only 3 of the usages have occurrence specific information. The occurrences tab will only display 3 rows, one for each named occurrence.
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Occurrences are also be displayed in the part structure pane on the left by selecting Display > Show Occurrences from the Viewing action set in the toolbar. For more information about the Viewing action set, see Viewing Action Set - Parts.
The following table describes the part attributes shown in the default table view on the Occurrences tab. For a detailed description of all part attributes, see Part Attributes.
Attribute
Description
Number
The unique numeric identifier for the part. This attribute may be automatically supplied by a standard part number generator when parts are created in your system.
Name
The text identifier for the part. Does not have to be unique.
Reference Designator
An alphanumeric code used to identify individual occurrences of a part used within a product structure.
Location
The numeric value that specifies the location for an occurrence. Specify the values for the X, Y, and Z Point and Angle fields. These values are copied to the Location field, and the other way round. Also, when you update or remove the values for the Point and Angle fields, they are updated or removed in the Location field. The unit of measure for the X, Y, Z point and the X, Y, Z angle is determined by the measurement system that you specify.
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This field is available only when the Allow pasting location to occurrence preference is enabled.
For more information about editing operations available in the Occurrences tab, see Editing in the Occurrences Tab.