Data Reference Guidelines

Attributes allow elements to reference calculations and PI tags through the configuration of a data reference. Data references are plug-ins to the AF and allow data to be populated from automated field data collection and business systems. You can configure one of the data references for each Attribute in an element. When the Element is then used in a Model analysis, the analysis receives the value through the data reference. An analysis can send output results through a data reference, as well as receive values as inputs. If an Attribute does not use a data reference, then the value that it holds is a static value.

The following table lists the available data references with Sigmafine and some information about how they are used in Sigmafine elements.

Guidelines for Specifying Data References

Data Reference	Description
Components	This data reference performs calculations needed for chemical component balances. Use it to configure the analyzer components for each analyzer element. See the Components Data Reference section for more information.
Formula	Use the Formula Data Reference to create a custom calculation. This calculation can be one formula or a sequence of calculations. This data reference can have many input Attributes used in the calculation. See the Formula Data Reference section for more information.
PI Point	Use the PI Point Data Reference to retrieve or send data with PI points (tags). Attributes that are marked as input to the analysis are typically read only. See the PI Point Data Reference section for more information.
Sigmafine	Use the Sigmafine Data Reference for different types of correction factors needed for Sigmafine analyses. Examples of these calculations are volume correction factor (VCF) and Gas Meter Compensation. See the Sigmafine Data Reference section for more information.
Table Lookup	The Table Lookup Data Reference provides a convenient way to look up data in one of the database tables. The tables themselves can be static values or are the result of SQL based query to an external database. See the Table Lookup Data Reference section for more information.
Tank Volume from Gauge	Use the Tank Volume from Gauge Data Reference to calculate tank volume from a gauge reading. Multiple methods are supported to calculate the volume. See the Tank Volume from Gauge Data Reference section for more information.
UOM (Unit-of-Measure)	Use the Unit of Measure Data Reference for class-to-class UOM conversions. It contains all class-to-class conversions needed by Sigmafine. For example, this can be used to derive a mass from a volume and density. See the Unit of Measure Data Reference section for more information.
Previous Value	Use the Previous Value Data Reference to use the values of Elements and Attributes of a previous Case in the current case. See the Previous Value Data Reference section for more information.