ABB RELION Series, Руководство по протоколу связи

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Some DNP3 analog input points, such as CT/VT measurement values, support
primary and secondary scaling. This selection can be done in PCM600 by selecting
either "Primary value" or "Secondary value" for
Representation . If the analog input
object does not support primary and secondary scaling, the selection does nothing.
The DNP3 analog input event buffer size is 150.
In case of analog events, the IED system produces changed analog events with a
specific sampling rate and deadband. The sampling rate and deadband can be
additionally modified for DNP3 AI points through the Communication Management
tool in PCM600. If a DNP3 analog input points' additional
Deadband value is set to
“0.0”, the IED system analog events are propagated as such through the DNP3
protocol. Sampling rate of the DNP3 AI value can also be reduced through the points'
Deadband Time setting. This means that the events are transmitted less frequently. If
Deadband Time is for example set as “2”, then analog events are not produced more
frequently than with two seconds interval from the DNP3 AI object.
3.5.4 Counter objects
DNP3 counter objects (object type 20) are derived from the relay's IEC 61850 object
class BCR. For each counter, there is also a frozen counter value available for reading
as object type 21.
There are two types of counters in the relay.
• BCR class is an integrated totals type counter, typically used for energy values.
• INC class counters are operational counters, for example, circuit breaker control
counters.
It is possible to freeze and reset the DNP3 counters in this relay. However, the original
BCR counters will also be reset. Another method is to read the cumulative values and
not reset the counters.
The DNP3 Counter, and Frozen Counter event buffer size is 30.
3.5.5 Binary outputs and control relay output block
DNP3 binary outputs (Object group 10) are cross-coupled with the protection relay’s
IEC 61850 control data classes SPC and DPC. The DNP3 stack automatically handles
the conversion between the two protocols’ control models.
DNP3 control is never done directly to the binary outputs but rather indirectly using
the Control Relay Output Block (CROB) function. The CROB function contains some
additional information regarding the control sequence, for example, pulse-length and
number of control pulses. These parameters are intended for RTU type (non-
intelligent) DNP3 devices. However, in this protection relay, all the required control
parameters are already configured properties of the control object. Therefore most
control parameters given in the DNP3 CROB command are neglected by the
protection relay. Only the control direction is noticed. Most single point objects, like
1MRS758757 A
Section 3
Vendor-specific implementation
REC615 and RER615 21
Communication Protocol Manual