J.4
SEL-311C Relay Instruction Manual Date Code 20060320
MIRRORED BITS Communications
Operation
Use the COM 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.
When channel unavailability exceeds a user-settable threshold, the relay will
assert a user accessible flag, hereafter called CBADx.
Relay disabled Relay protection functions disabled as during power up
or change in settings or settings group.
Loop Back Loop back enabled. Error conditions followed by “(L)” occurred while
the system was in loop back.
Framing error The UART did not detect a stop bit in the received M
IRRORED BITS data.
Table J.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.
To Next Page
