scheider electric MiCOM P746, Technical Manual

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P746/EN SC/G31 SCADA Communications
(SC) 13-
34
MiCOM P746
SC
5. DNP3.0 INTERFACE
5.1 DNP3.0 protocol
The descriptions given here are intended to accompany the device profile document that is
included in the menu database, P746/EN MD. The DNP3.0 protocol is not described here,
please refer to the documentation available from the user group. The device profile
document specifies the full details of the DNP3.0 implementation for the relay. This is the
standard format DNP3.0 document that specifies which objects, variations and qualifiers are
supported. The device profile document also specifies what data is available from the relay
via DNP3.0. The relay operates as a DNP3.0 slave and supports subset level 2 of the
protocol, plus some of the features from level 3.
DNP3.0 communication uses the EIA(RS)485 or fiber optic communication port at the rear of
the relay. The data format is 1 start bit, 8 data bits, an optional parity bit and 1 stop bit.
Parity is configurable (see menu settings below).
5.2 DNP3.0 menu setting
The settings shown below are available in the menu for DNP3.0 in the ‘Communications’
column.
Setting Range Description
Remote Address 0 – 65534 DNP3.0 address of relay (decimal)
Baud Rate
1200, 2400, 4800,
9600, 19200, 38400
Selectable baud rate for DNP3.0
communication
Parity None, Odd, Even Parity setting
Time Sync. Enabled, Disabled
Enables or disables the relay requesting time
sync. from the master via IIN bit 4 word 1
5.3 Object 1 binary inputs
Object 1, binary inputs, contains information describing the state of signals within the relay
which mostly form part of the digital data bus (DDB). In general these include the state of
the output contacts and input optos, alarm signals and protection start and trip signals. The
‘DDB number’ column in the device profile document provides the DDB numbers for the
DNP3.0 point data. These can be used to cross-reference to the DDB definition list that is
also found in the menu database, P746/EN MD. The binary input points can also be read as
change events via object 2 and object 60 for class 1-3 event data.
5.4 Object 10 binary outputs
Object 10, binary outputs, contains commands that can be operated via DNP3.0. As such
the points accept commands of type pulse on [null, trip, close] and latch on/off as detailed in
the device profile in the menu database, P746/EN MD and execute the command once for
either command. The other fields are ignored (queue, clear, trip/close, in time and off time).
Due to that fact that many of the relay’s functions are configurable, it may be the case that
some of the object 10 commands described below are not available for operation. In the
case of a read from object 10 this will result in the point being reported as off-line and an
operate command to object 12 will generate an error response.
Examples of object 10 points that maybe reported as off-line are:
−
Activate setting groups - Ensure setting groups are enabled
−
CB trip/close - Ensure remote CB control is enabled
−
Reset NPS thermal - Ensure NPS thermal protection is enabled
−
Reset thermal O/L - Ensure thermal overload protection is enabled
−
Reset RTD flags - Ensure RTD Inputs is enabled
−
Control Inputs - Ensure control inputs are enabled