Writable Data Objects; Control Relay Output Block Parameters; Direct Operate And Select Before Operate - ABB RELION Series Communication Protocol Manual

1MRS758757 A
3.4.3
3.4.3.1
3.4.3.2
REC615 and RER615
Communication Protocol Manual
• The event buffering is handled by DNP3 object type, but a possible event
overflow signal is in turn given from the DNP3 event class. If a class only
contains a particular object type, the overflow occurs for that DNP3 object type.
• In unsolicited reporting mode, the controlling station enables the classes that
should start the spontaneous event reporting. One or some of the classes could
then be left disabled.

Writable data objects

Writable objects belong to object types 10 (binary outputs) and 40 (analog outputs).
Outputs are controlled through the control relay output block or analog output block
commands. From the DNP3 output objects, the commands are propagated further to
the native IEC 61850 control objects.

Control relay output block parameters

Controlling of the native IEC 61850 objects differs from the way that an RTU control
operation is defined by the DNP3. In DNP3 standard, it is assumed that the controlling
station decides the control type (pulse or persistent), pulse lengths and possible pulse
trains (number of pulses). These control parameters are given to the RTU outstation
in the CROB command. In IEC 61850 standard, the same parameters and few
additional parameters are configured as properties of the control objects. The control
command issued to the control object is only a trigger. In a protection relay, the control
object knows how to perform the physical control operation.
In CROB data, the given pulse type and pulse length values are ignored by the
outstation. The only data that is checked by the outstation is the direction (ON or
OFF). If the IEC 61850 data object is of persistent type, OFF is also possible. When
controlling a double-pole IEC 61850 data object, the direction information is used.

Direct operate and select before operate

Both direct operate and select before operate DNP3 control functions are supported
for binary outputs.
In the native IED IEC 61850 data, these control operation differences are referred to
as the control model. The control model is in turn configured as a property of the
control object. Thus an IEC 61850 control object can be either in "Direct" or "SBO"
mode. This is applicable for double-point control objects. Single point control objects
in the protection relay always work in "Direct" mode. Depending on the control model
setting of the native IEC 61850 control object, various DNP3 control functions can be
performed.
Table 2: Available control models
IEC 61850 control model
Direct
SBO
1) Configurable with the Communication Management tool
Vendor-specific implementation
Supported DNP3 control function
Direct only
1)
Direct or SBO
Section 3
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