Schweitzer Engineering Laboratories SEL-351-5, Instruction Manual

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I.4
SEL-351-5, -6, -7 Relay Instruction Manual
Date Code 20070117
M
IRRORED
B
ITS
(in Firmware Versions 6 and 7)
Operation
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 RBAD
x .
When channel unavailability exceeds a user-settable threshold, the relay will
assert a user accessible flag, hereafter called CBAD
x .
Re-sync The M
IRRORED
B
ITS
device at the other
end of the link detected an error.
Data error Received data was not self-consistent, or the address was wrong.
Relay disabled Relay protection functions disabled as during power up
or change in settings or settings group.
Loop Back Loopback enabled. Error conditions
followed by “(L)” occurred while the system was in loopback.
Framing error The UART did not detect a stop bit in the received M
IRRORED
B
ITS
data.
Table I.1 Error Types Reported by the Communications Report (Sheet 2 of 2)
Error Type Description
NOTE:
The user will typically
combine RBADx with other alarm
conditions using SEL
OGIC
control
equations.
NOTE:
The user will typically
combine CBADx with other alarm
conditions using SEL
OGIC
control
equations.