Rockwell Automation FactoryTalk Historian SE DataLink 4.2 User Guide - Manual (Page 115)

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Supplementary Information
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Array and Cell Limits
FactoryTalk Historian DataLink is subject to an Excel limitation on the
number of elements in a calculation array. The maximum numbers of
values that can be returned for a single FactoryTalk Historian function, per
retrieval are:
 65,536 for Excel XP-2003.
 1,048,576 for Excel 2007 and later.
The Excel SDK used by FactoryTalk Historian DataLink limits strings to
255 characters in length for Excel XP and later. Input strings for
FactoryTalk Historian DataLink expressions in a referenced cell may not
exceed this 255 character limit.
Similarly, string output such as FactoryTalk Historian tag name strings
may be truncated by FactoryTalk Historian DataLink to 255 characters.
Row Limitations
FactoryTalk Historian DataLink 4.x can utilize all one million rows in a
single Microsoft Excel spreadsheet. Data up to this limit may be retrieved
in one or more function arrays.
To retrieve very large amounts of data from FactoryTalk Historian, users
may need to configure the ArcMaxCollect parameter on their
FactoryTalk Historian server. The default value is 150 thousand rows.
Note that a query can exceed a maximum limit even though it returns a
relatively small number of values. What counts is the real number of events
called from FactoryTalk Historian archives. For example, sinusoid tag
values vary constantly between 0 and 100. A query for sampled values of
sinusoid every 30 seconds over a year, with filter expression excluding all
values less than 95 may return a relatively small number of values, but
many more events are retrieved from the archives as the query is
processed.