Spirit flow-x, Справочник по функциям

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Flow-X─ Function Reference
4-213
Flow-X General functions - fxIndex
fxIndex
The 'fxIndex' provides the same functionality as the Excel Index function with the addition of the
creation of tag names.
A spreadsheet cell that contains a 'fxIndex' function obtains the tag name as defined by its 'Name' input
with the tag inheriting all properties including the value and units from the referred tag.
When the referred cell contains a writable tag (i.e. a value and no function) than the cell with the
'fxIndex' function also represents a writable tag with the same properties.
When the referred cell contains a tag that represents one or more alarms, then the same alarms are
created for the cell with the 'fxIndex' function.
The 'fxIndex' is especially useful for setting up generic (template) applications as illustrated by the
following examples:

For each of the 6 analog inputs the application contains one 'Analog input' function that
generates tag names with prefix, "AIN1_", "AIN2_ etc. Also more meaningful tag names
such as "..PT" (pressure transmitter), ".._TT" are used in the application. When changing the
high alarm limit for the pressure transmitter (e.g. through an OPC interface) it makes more
sense to address the tag as "..PT_HISCALE" instead of "..AIN3_HISCALE" (assuming AIN 3
being used for the pressure transmitter). This can be achieved by using the 'fxIndex' function
for the cell that represents the '..PT_HISCALE' tag.

In some cases one and the same input signal is used for multiple process variables that are
defined in the generic application. E.g. when the generic application assumes a prover inlet
temperature input signal as well as a prover outlet temperature signal (and has
corresponding tag names), while there is only a temperature transmitter in the prover loop,
then the input tags of both signals can refer to the same "AIN" signal by using the 'fxIndex'
function.
Function inputs Remark EU SW tag Range Default
Name Tag name for the cell that contains
the function
Reference Reference to one or more cell
ranges 1
Row number Optional
Number of the row in reference
from which to return a reference 1
Column number Optional.
Number of the column in reference
from which to return a reference 1
Area number Optional
Selects a range in reference from
which to return the intersection of
'Row number' and 'Column
number'. The first area selected or
entered is numbered 1, the second
is 2, and so on. 1
Function
outputs Remark EU SW tag Alarm Fallback
Value The cell obtains a tag name that consist
of the prefix as defined by input 'Name'
with the addition of the suffix as was
generated for the tag that is being
referred to.
The same applies for an alarm if one has
been defined for the referred tag. Same
as
referred
cell See
Remark