Areva MiCOM P921, Technical Manual

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P92x/EN CT/E11 Technical Guide
Courier Database
Page 80/118 MiCOM P921-P922-P923
2.5.3 Event Format
The Send Event Command results in the return of the following fields by the relay:
·
Cell Reference
· Time stamp
·
Cell text
· Cell value
The table in paragraph 1.2.2 (list of events created by the relay) indicates how the
content of the above mentioned fields are interpreted. The fault event will return a
Courier Type 3 event which contains the above fields together with two additional
fields:
·
Event extraction column
· Event number
These fields contain additional information which are extracted from the relay using
the referenced extraction column. Row 01 of the extraction column contains a setting
which allows the selection of the fault record. This setting should be set to the event
number value returned within the record, the extended data can be extracted from
the relay by uploading the text and data from the column.
2.5.4 Manual record Extraction
Column 02 of the database can be used to manually view the fault records. The
contents of this column will depend of the nature of the record selected. It is possible
to select directly a fault record.
Fault record selection (Row 01) – this cell can be used to directly select a fault
record using a value between 0 and 4 to select one of the five stored fault records (0
will be the most recent fault while 4 is the oldest one). The column will then contain
the details of the fault record selected ( row 02 to 0A).
It should be noted that if this column is used to extract event information from the
relay, the number associated with a particular record will change when a new fault
occurs.
2.6 Disturbance Record Extraction
The stored disturbance records within the relay are accessible via the Courier
interface.
Select Record Number (Row 01) – this cell can be used to select the record to be
extracted. Record 0 will be the oldest un-extracted record, older records will be
assigned positive values, and negative values will be used for more recent records.
To facilitate automatic extraction via the rear port, the disturbance bit of the Status
byte is set by the relay whenever there are un-extracted disturbance records.
Once a record has been selected, using the above cell, the time and date of the
record can be read from the cell 02. The disturbance record itself can be extracted
using the block transfer mechanism from cell B00B .
As it has been stated, the rear Courier port can be used to automatically extract
disturbance records as they occur. This is possible when using the standard Courier
mechanism defined in chapter 8 of the Courier User Guide.