G-14 Distributed Network Protocol (DNP3) Date Code 20080110
SEL-387E Instruction Manual
Binary inputs (objects 1 and 2) are supported as defined by the previous table. Binary inputs
0–799 and 1600–1619 are scanned approximately once every 128 ms to generate events. When
time is reported with these event objects, it is the time at which the scanner observed the bit
change. This may be significantly delayed from when the original source changed and should
not be used for sequence-of-events determination. In order to determine an element’s point
index, see the Binary Input Lookup Table. It is derived from the Relay Word Bits tables in
Section 4: Control Logic. Locate the element in question in the table and note the Relay Word
row number. From that row number, subtract the row number of the first Relay Word row
(usually 2) and multiply that result by 8. This is the index of the right-most element of the Relay
Word row of the element in question. Count over to the original element and add that to get the
point index. Binary Inputs 800–1599 are derived from the Sequential Events Recorder (SER)
and carry the time stamp of actual occurrence. Add 800 to the Binary Input Point column to get
the point mapping for points 800–1599. Static reads from these inputs will show the same data
as a read from the corresponding index in the 0–799 group. Only points that are actually in the
SER list (SET R) will generate events in the 800–1599 group.
Analog Inputs (objects 30 and 32) are supported as defined by the preceding table. The values
are reported in primary units. Current magnitudes are scaled according to the DECPLA setting,
voltage magnitudes by DECPLV, and other magnitudes by DECPLM. For example, if DECPLx
is 3, then its value is multiplied by 1000. Event-class messages are generated whenever an input
changes beyond the value given by the appropriate analog dead-band setting (ANADBA,
ANADBV, ANADBM). The dead-band check is done after any scaling is applied. The angles
will only generate an event if, in addition to their dead-band check, the corresponding magnitude
(the preceding point) contains a value greater than the value given by the dead-band setting.
Analog inputs are scanned at approximately a half-second rate, except for analogs 159–177.
During a scan, all events generated will use the time the scan was initiated. Analogs 159–177
are derived from the history queue data for the most recently read fault and do not generate event
messages. Analog 159 is defined as follows:
Value Event Cause
1 Trigger command
2 Pulse command
4 ER element
16 Trip 4
32 Trip 3
64 Trip 2
128 Trip 1
If Analog 159 is 0, no more new events are available (i.e., all events have been read).
Control Relay Output Blocks (object 12, variation 1) are supported. The control relays
correspond to the remote bits and other functions, as shown above. The Trip/Close bits take
precedence over the control field. If either the Trip or Close bit is set, one of the other control
field bits must be set as well. The control field is interpreted as follows:
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