ABB RELION Series, Communication Protocol Manual

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The Analog Output Block DNP3 object group (41) is used for writing to a DNP3
analog output. Analog output can be also read from the protection relay, as object
group 40. Reading an analog output returns the last written value to the object.
Class events are generated for changed Analog Output values. The DNP3 Analog
Output event buffer size is 100.
3.6 Fault records
Fault record data objects contain registered values captured simultaneously by the
relay's protection at the moment of a fault. The fault record objects internally belong to
IEC 61850 logical node FLTRFRC1.
The FLTRFRC1 objects can be found as DNP3 analog input values in the DNP3 point
list. There are two alternative DNP3 data objects for each captured fault record object
in the point list. A different trailing text for the objects is shown in the object's name,
either “Ev-Upd” (event updated) or “Record” (read on demand).
3.6.1 Ev-Upd type objects
A freely selectable part of the “Ev-Upd” objects, or alternatively all objects can be
added to the DNP3 analog input data memory map. These objects can also be enabled
for DNP3 class events. Each time a new fault record capture is done by the protection
relay, the objects are sent as DNP3 class events to the controlling station. Every object
captured at the same time (belonging to the same record) has the same time tag. The
controlling station can also, at any time, read fault record objects from the outstation.
The most recent (newest) captured value is always returned.
The deadband setting for the “Ev-Upd” objects should be “0”. This means that every
update of the object from the protection relay level is propagated as a DNP3 class
event, regardless of the change in value. As a default setting, all analog inputs have
deadband setting of 0.0, that is, the event is always reported when a system event is
generated. In the fault record, the next captured value can be identical to the previous
one, therefore the recommended deadband value is 0.0.
3.6.2 Record type objects
The protection relay saves the 128 latest captured fault records internally. On demand,
these (older) records can be read by the DNP3 controlling station.
A freely selectable part of the “Record” objects can be added to the DNP3 analog input
data memory map. These objects are as default defined as ‘Static only’. This means
that they can only be read on demand by the controlling station. Also notice the analog
output object from the same logical node named FLTRFRC1.SelRow.ctlVal ‘-Select
record’. This object should be added to the DNP3 analog output area.
1MRS758757 A
Section 3
Vendor-specific implementation
REC615 and RER615 23
Communication Protocol Manual