InstrumentTag

Length

Depending on the version of the PI API and the PI Data Archive, this interface supports Tag attributes whose length is at most 255 or 1023 characters. The following table indicates the maximum length of this attribute for all the different combinations of PI API and PI Data Archive versions.

If the PI Data Archive version is earlier than 3.4.370.x or the PI API version is earlier than 1.6.0.2, and you want to use a maximum tag length of 1023, you need to enable the PI SDK.

Note: If using the DeltaV OPC Alarms and Events Server, please read the Appendix B: DeltaV OPC Alarm and Events Server ® section carefully before configuring interface tags.

Several attributes are associated with an OPC alarm or event. Any or all these attributes can be archived, and must be specified as a PI tag. Use the Instrument Tag attribute to configure the Alarm/Event source in the OPC AE server. Use a specification of area as a prefix to the source by using the delimiter specified by the OPC AE server as a separator, as shown in these examples. In most cases, the configuration tool will specify the source with the appropriate separator for the server. It is recommended that source names be unique. If source names are not unique then the area needs to be specified along with the source and separated by the proper separator character.

The interface also supports the use of an asterisk (*) on the end of a source or area name. This character is used as a wildcard character and tells the interface to match all sources that meet the specified criteria up to the asterisk. Note that the wildcard character can only be used on the end of the area or source name.

/ALL – This directive specifies ALL sources and directs the interface to archive all events generated by the OPC AE server to this PI tag. This configuration should not be used in a production environment. It was designed for testing and validating a setup and should be used for testing purposes only.

Note: The /ALL tag configuration is designed for testing purposes and should NOT be used in a production environment.

FIC1001 – Specifies only the source.

FIC* – Specifies all sources beginning with “FIC”.

Boiler1.FIC1001 – Specifies the area and source where the separator is a dot.

Boiler1\FIC1001 – Specifies the area and source where the separator is a backslash

Boiler1* – Specifies all sources from the area named “Boiler1”.

Note: When specifying the asterisk (*) for wildcards the /wc startup command needs to be specified in the startup file. See Startup Command File.