BE1-951
Reporting and Alarm Functions
6-15
Table 6-7. Legend for Figure 6-1
Call-Out
Description
A
A fault summary report and an oscillograph record is triggered when either the SG-TRIGGER
pickup or logic expression becomes TRUE.
B
During the time that the SG-TRIGGER trip expression is TRUE, targets are logged from each
of the protective functions that reach a trip state. If a protective function is not being used for
tripping purposes, the associated target function can be disabled through the SG-TARG
setting.
C
Fault clearing time is calculated as the duration of the time that either the SG-TRIGGER
pickup or logic expression is TRUE.
D
Breaker operate time is calculated as the time from when the SG-TRIGGER trip expression
becomes TRUE until the fast-dropout current detector senses that the breaker has
successfully interrupted the current in all poles of the breaker.
E
A second oscillographic record is triggered to record the end of the fault if the SG-TRIGGER
pickup or logic trigger expression remains in the true state at the time that the first
oscillographic record ends. This second record will have from ¼ to five cycles of pre-trigger
data depending upon when both the SG-TRIGGER pickup and logic expressions become
false
F
Recorded fault current, voltage, and distance magnitudes are displayed on the target screen
of the optional HMI. The same information including current and voltage angles are recorded
in the fault summary report. The magnitude, angle, and distance results are based on data
captured two cycles after the trip output goes true. This two-cycle delay allows the line
transients to settle to provide more accurate data. The post fault current vectors are
compared to pre-fault current vectors captured three cycles prior to protective pickup to
perform distance calculations. If the SG_TRIGGER TRIP expression does not become true,
the fault was cleared by a down stream device. For these pickup only events, fault current,
voltage, angle, and distance recorded in the fault summary report will be for the power
system cycle ending two cycles prior to the end of the fault record. This is also the case if
the fault record was triggered through the ASCII command interface by the RF_TRIG
command.
G
During the time that the SG-TRIGGER pickup expression is TRUE, the red Trip LED on the
front panel flashes indicating that the relay is picked up.
H
During the time the SG-TRIGGER trip expression is TRUE, the red Trip LED on the front
panel lights steadily indicating that the relay is in a tripped state. If targets have been logged
for the fault, the Trip LED is sealed in until the targets have been reset.
I
Breaker operations and interruption duty functions are driven by the breaker status function.
The operations counter is incremented on breaker opening. The magnitude of the currents
that are used for accumulating breaker duty are recorded for the power system cycle ending
when the breaker status changes state. Thus, breaker duty is accumulated every time that
the breaker opens even if it isn’t opening under fault.
J
Setting group changes are blocked when the SG-TRIGGER pickup expression is TRUE to
prevent protective functions from being reinitialized with new operating parameters while a
fault is occurring.
