Schweitzer Engineering SEL-351P, Быстрый старт

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Date Code 990430 M
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SEL-351P Manual Técnico
Loop-Back Testing
Use the LOOP command to enable loop-back testing.
While in loop-back mode, ROKx is deasserted, and another user accessible flag, LBOKx, will
assert and deassert based on the received data checks.
Channel Monitoring
Based on the results of data checks described above, the relay will collect information regarding
the 255 most recent communications errors. Each record will contain at least the following
fields:
•
Dropout Time/Date
•
Pickup Time/Date
•
Time elapsed during dropout
•
Reason for dropout (See Message Decoding and Integrity Checks)
Use the COMM command to generate a long or summary report of the communications errors.
There is only a single record for each outage, but an outage can evolve. For example, the initial
cause could be a data disagreement, but the outage can be perpetuated by framing errors. If the
channel is presently down, the COMM record will only show the initial cause, but the COMM
summary will display the present cause of failure.
When the duration of an outage exceeds a user-settable threshold, the relay will assert a user-
accessible flag, hereafter called RBADx. Note: The user typically will combine RBADx with
other alarm conditions using SEL
OGIC
Control Equations.
When channel unavailability exceeds a user-settable threshold, the relay will assert a user
accessible flag, hereafter called CBADx. Note: The user typically will combine CBADx with
other alarm conditions using SEL
OGIC
Control Equations.
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™ P
ROTOCOL FOR THE
P
ULSAR
9600 B
AUD
M
ODEM
The user indicates that a Pulsar MBT modem is to be used by responding "MBT" to the
RTS/CTS setting prompt. When the user selects MBT, the baud rate setting will be limited 9600
baud.
The M
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protocol compatible with the Pulsar MBT-9600 modem is identical to the
standard M
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protocol with the following exceptions:
The relay injects a delay (idle time) between messages. The length of the delay is one relay
processing interval. Note: An idle processing interval guarantees at least 19 idle bits at 9600
baud in an SEL-321 Relay with the system frequency at 65 Hz.
The relay resets RTS (to a negative voltage at the EIA-232 connector) for M
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communications using this specification. The relay sets RTS (to a positive voltage at the
EIA-232 connector) for M
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communications using the R6 or original R version of
M
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.