Regardless of whether Numeric or Text is selected for the calculation type, you can insert FRACAS, Prediction, and Maintainability assembly result fields in user-defined calculations. When you select System Tree Items as the table type in the Calculation Editor pane, the data fields that you can insert in the equation include calculation result fields for the module for which you are defining a custom calculation.

For example, if Prediction is the module selected, the list of fields that you can insert for the System Tree Items table includes Prediction calculation result fields, such as Failure Rate, DormantFailure Rate, Mean; and Failure Rate, Mission. This list does not include FRACAS calculation result fields, such as Mean 1 (FRACAS), Mean 2 (FRACAS), and Mean 3 (FRACAS). When necessary to avoid confusion, the source of the calculated result field is noted in parentheses after the field name.

You cannot store the results for a user-defined calculation in a result field for a predefined calculation. Windchill Risk and Reliability always uses the result stored for the selected configuration in your custom calculation. Therefore, it is recommended that you insert result fields in user-defined calculations only if System files have a single configuration.

Multiple configurations can exist in a System file only if you have turned on the Configurations table in the Table Settings pane in the Project Properties window. For more information, see Table Settings (Project).

If the configuration cannot be determined, the first configuration in the Configurations table is used for user-defined calculations. This is the configuration with the lowest record number. For more information, see Configurations Table.

For a FRACAS calculation operating on records in a FRACAS table or subtable, a configuration is tied to the current record. However, this configuration is not used. The configuration currently selected in the Configurations table is used. Again, it is recommended that you use result fields in user-defined calculations only in System files with single configurations.

User-defined calculations with calculation results fields cannot be performed automatically. When you insert a calculation result field in a user-defined calculation, Calculate Automatically becomes unavailable in the Calculations pane.