The function has the following alarm signals:
•
MUDATA: Indicates when sample sequence needs to be realigned. that is the
application soon needs to be restarted. The signal is raised to 2 s before the
application is restarted.
•
SYNCH: Indicates that the time quality of the hardware is out of the set value
from parameter
synchAccLevel
(
1 μs
,
4 μs
or
unspecified
) and the parameter
AppSynch
is set to
Synch
. In case of
AppSynch
is set to
NoSynch
the SYNCH
output will never go high.
•
SMPLLOST: Indicates that more than one sample has been lost/been marked
invalid/ overflow/ been marked failed, and the sample has thereafter been
substituted. When SMPLLOST is high, protection is blocked.
•
MUSYNCH: Indicates that the MU connected is not synchronized. Received from
quality flag in datastream. No IED setting affects this signal.
•
TESTMODE: Indicates that the MU connected is in
TestMode
. Received from
quality flag in datastream. No IED setting affects this signal.
Timeout
TSYNCERR Indicates that there is some timeout on any configured time source or the
time quality is worse than specified in SynchAccLevel. The timeout is individually
specified per time source (PPS, IRIG-B, SNTP etc.) See section
Blocking condition
Blocking of protection functions is indicated by (SAMPLOST is high) or (MUSYNCH
is high and
AppSynch
is set to
Synch
) or (SYNCH is high)
Application synch is not required for differential protection based on ECHO mode. A
missing PPS however will lead to a drift between MU and IED. Therefore protection
functions in this case will be blocked.
17.3.3
Consequence on accuracy for power measurement functions
when using signals from IEC 61850-9-2LE communication
The Power measurement functions (CVMMXN, CMMXU, VMMXU and VNMMXU)
contains correction factors to account for the non-linearity in the input circuits, mainly
in the input transformers, when using direct analogue connection to the IED.
The IED will use the same correction factors also when feeding the IED with analog
signals over IEC 61850-9-2LE. Since the signals via IEC 61850-9-2LE are not subject
to the same non-linearity errors this will cause an inaccuracy in the measured values.
For voltage signals the correction factors are less than 0.05% of the measured value
and no angle compensation why the impact on reported value can be ignored.
Section 17
1MRK505222-UUS C
Station communication
1004
Technical reference manual
Summary of Contents for Relion 670 series
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