Interface Collection Mechanism; Point Push For Digital Data; Point Push For Analog Data - Emerson PACSystems RX3i User Manual

User Manual
GFK-2911E

Interface Collection Mechanism

Based on the Record Format in Section 6.4.2, the following is the process for pushing points
into the EDS001:
• IF words [000] and [002] are non-zero, a point push is in operation is processing, or has
ended in an error.
• IF words [000] and [002] are both 0 a point push can start.
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• If words [000], [001], [002] are all -1 (65535) then a Point Push has been detected by
the EDS001 and is in process. Note: Point Push works over many PLC scans, so the ladder
logic can take up to three scans to complete.
• If words [000] and [002] are both 0, the push is complete. Word [001] will revert to the
same sequence number pushed. A new Point Push record can now be initiated.
• The Point Push interface will HOLD if no event space is available and will not accept any
point push records, the step where the three records are set to -1 will not occur, and the
header information will remain the same as that entered by the user's application code.
You can retry a Point Push but be aware that some of the Point Push records may have
transferred successfully to the EDS001 database, since the EDS001 Point Push interface
checks the Point Push data as it processes. An invalid point number, or object, will cause the
Point Push to terminate, once discovered.

Point Push for Digital Data

When using point push for Digital data, COMMREQ parameter 17, bits 13 and 14 allow the
entire range of points for an object to start in Point Push mode, taking a single snap-shot of
the point values at start, and not marking the points as having changed. This is used when
the Point Push interface is being used with the Soft SOE block application, so as not to detect
change of data repeatedly for the same point, same value at startup.

Point Push for Analog Data

When using point push for Analog data, the following rules need to be observed for the data
to be interpreted correctly by the EDS001 module code, as the variance specified, and the
default variance have a correlation to the data interpretation.
The Variance for the point must be set using the following table.
Configuration of DNP3 outstation Parameters
Fill the DNP3 records into the table
In word [002] place the number of records to be pushed (1 to 8)
In word [000] place the Number 1235
In word [001] place a non-zero number, that is not the same as the contents of status
word 92. This is the trigger for the Point Push operation. NOTE: this word is an
unsigned integer, so you can simply ADD_UINT 1 to the value in the status word, and
if 0 add again.
Chapter 6
Sep 2019
49