Rockwell Automation 1756-HIST2G FactoryTalk Historian ME 2.2 - Manual (Page 317)

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G LOSSARY
FactoryTalk Historian
ME server The set of several software subsystems packaged together that
constitute a single logical server application capable of storing
time-series data from distributed data sources and serving this
same data to client applications in real-time.
FactoryTalk Security A set of security services are fully integrated into the
FactoryTalk Directory.
Fixed Archive A type of archive file that allocates all of its disk space at
creation time. Thus, both an empty and full archive occupy the
same amount of disk space. Unless shifting has explicitly been
disabled, non-empty fixed archives will participate in archive
shifts.
Ladder Logic A program written in a format resembling a ladder-like
diagram. A programmable controller uses this program to
control devices.
LED Light emitting diode. It is used as a status indicator on the
module.
NAND The NAND Flash architecture is one of two flash technologies
(the other being NOR) used in memory cards such as the
CompactFlash cards used to upgrade the module firmware.
NAND is best suited to a flash device requiring high capacity
data storage. This is the data storage architecture for
FactoryTalk Historian ME.
Offset An optional field used when defining a scan class that specifies
the first time at which a scan should occur. If no offset is
specified, the first scan occurs immediately after the specified
interval. After the initial scan, subsequent scans continue to
occur after every specified interval.
Out of Order Event An incoming event whose timestamp is prior to the timestamp
of the event currently residing in the Snapshot table for a
particular point. All such events bypass compression and are
written directly to the event queue.
Term Definition