Rockwell Automation FactoryTalk Historian SE 3.0 UniInt Interface User Guide - Manual (Page 26)

Historian Point Configuration
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or equal to the Zero attribute and less than or equal to the Zero attribute plus the
Span attribute.
The TypicalValue must be between Zero and Zero plus Span. For digital points, Historian
sets the Zero and Span internally. See the description of Zero and Span attributes for more
information.
SourceTag
The SourceTag attribute is used to designate a trigger tag for output points. The mechanism
by which a SourceTag is used to trigger outputs is discussed under the section called ―Output
Points,‖ page 23.
Shutdown
The shutdown attribute is used only if the server node is a Historian 3 system.
The Shutdown attribute is 1 (true) by default. The default behavior of the Historian
Shutdown subsystem is to write the SHUTDOWN digital state to all Historian Points when
Historian is started. The timestamp that is used for the SHUTDOWN events is retrieved from
a file that is updated by the Snapshot Subsystem. The timestamp is usually updated every 15
minutes, which means that the timestamp for the SHUTDOWN events will be accurate to
within 15 minutes in the event of a power failure. For additional information on shutdown
events, refer to the Historian Buffer Server.chm file.
Note: The SHUTDOWN events that are written by the Historian Shutdown subsystem
are independent of the SHUTDOWN events that are written by the interface when
the /stopstat command-line parameter is specified.
SHUTDOWN events being written to Historian can be disabled when Historian is restarted
by setting the Shutdown attribute to 0 for each point. Alternatively, the default behavior of
the Historian Shutdown Subsystem can be changed to write SHUTDOWN events only for
Historian Points that have their Shutdown attribute set to 0. To change the default behavior,
edit the \PI\dat\Shutdown.dat file, as discussed in Historian Server Reference Guide.
It is undesirable to write shutdown events when buffering is being used. Bufserv and
PIBufSS are utility programs that provide the capability to store and forward events to a
Historian Server, allowing continuous data collection when the Server is down for
maintenance, upgrades, backups, and unexpected failures. That is, when Historian is
shutdown, Bufserv will continue to collect data for the interface, making it undesirable to
write SHUTDOWN events to the Historian Points for this interface. Disabling Shutdown is
recommended when sending data to a Highly Available Historian Server Collective. Refer to
the Bufserv manual for additional information.