Schweitzer Engineering Laboratories SEL-351A, Руководство пользователя

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H.18
SEL-351A Relay Instruction Manual
Date Code 20080213
Distributed Network Protocol
Data Map
The Status field is used exactly as defined. All other fields are ignored. A
pulse operation asserts a point for a single processing interval. Caution should
be exercised with multiple remote bit pulses in a single message (i.e., point
count > 1), since this may result in some of the pulse commands being ignored
and returning an already active status.
Analog Outputs (objects 40 and 41) are supported as defined by the preceding
table. Flags returned with object 40 responses are always set to 0. The Control
Status field of object 41 requests is ignored. If the value written to index 0 is
outside of the range 1 through 6, the relay will not accept the value and will
return a hardware error status.
Relay Summary Event
Data
In standard mode (DNP) the Relay Event Summary data is available on a first
in, first out (FIFO) basis. In extended mode (DNPE) the Relay Event
Summary data can be read in two ways: first in, first out (FIFO); or last in,
first out (LIFO).
To use the FIFO method, the master should monitor binary input point 1023,
which will be on when there is an unread relay event summary. To read the
oldest relay event summary, the master should Pulse-On binary output
point 23. This will load the relay event summary analogs (points 105–113)
with information from the oldest relay event summary, discarding the values
from the previous load. After reading the analogs, the master should again
check binary input point 1023, which will be on if there is another unread
relay event summary. The master should continue this process until binary
input point 1023 is off. If the master attempts to load values using output point
23 when binary input point 1023 is off, the relay event type analog (point 105)
will be loaded with zero. With the FIFO method the relay event summaries
will always be collected in chronological order.
In extended mode (DNPE) only , the LIFO method is available. To use the
LIFO method the master should monitor binary input point 1023, which will
be set when there is an unread relay event summary. To read the newest relay
event summary, the master should Pulse-Off binary output point 23. This will
load the relay event summary analogs (points 105–113) with information from
the newest relay event summary, discarding the values from the previous load.
After reading the analogs, the master should again check binary input point
1023, which will still be on if there is another unread relay event summary.
The master should continue this process until binary input point 1023 is off. If
the master attempts to load values using output point 23 when binary input
point 1023 is off, the event type analog (point 105) will be loaded with zero.
With the LIFO method the relay event summaries will be collected in reverse
chronological order, unless binary input point 1025 is set, which the master
can use to identify when a newer relay event summary is available.
In extended mode (DNPE), DNP events are generated whenever the values in
points 105–113 change. Events are detected every second by the scanning
process. The master can collect relay event summaries using event data rather
than the static data polling described above. In order for this to work
31 Pulse RB16 Pulse RB15 Pulse RB16 Pulse RB15 Pulse RB16 Pulse RB15
32 Pulse CC Pulse OC Pulse CC Pulse OC Pulse CC Pulse OC
a
This function is only available in extended mode (DNPE). It functions as “Do Nothing” in standard mode (DNP).
Table H.9 Control Field (Sheet 2 of 2)
Index Close (0x4X) Trip (0x8X) Latch On (3) Latch Off (4) Pulse On (1) Pulse Off (2)
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