Siemens siprotec 7SA6, Manual

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Functions
6-310
7SA6 Manual
C53000-G1176-C156-2
Transmission
Statistics In 7SA6 the protection communication is registered in statistics. The delay times of the
information between the devices via interfaces (run and return) are measured steadily.
The values are kept stored in the Statistic folder. The availability of the transmission
media is also specified. The availability is indicated in %/min and %/h. This allows the
user to assess the transmission quality.
The operational measured values are also calculated in the event of a running fault
and approximately every 0.5 s.
Min/Max Values
and Average
Values Minimum, maximum and long-term average values are calculated by the 7SA6. Time
and date of the last update of the values can also be read out. At any time the
min/max values can be reset via binary inputs, via DIGSI
®
4 or via the integrated con-
trol panel. Additionally, the reset can be carried out cyclically, beginning with a preset
point of time.
The time period of the average value window and the number of updates can be set
for the long-term average values. The corresponding min/max values can be reset via
binary inputs, via DIGSI
®
4 or via the integrated control panel.
For an overview of the minimum, maximum and average values as well as their mean-
ing please refer to Subsection 6.23.6, “Average Calculation” and “Min/Max Values”
Limit Value /
Set Point
Monitoring
Use to detect about operating conditions. If a preset limit value / set point is exceeded,
an alarm is generated. This alarm can also be allocated to output relays and LEDs. In
contrast to the actual protection functions the monitoring function operates in the back-
ground; therefore it may not pick up if measured values are changed spontaneously
in the event of a fault and if protection functions are picked up. Since an alarm is only
output in case the limit value / set point is exceeded more than once, the monitoring
process cannot pick up directly before a trip.
Set points can be set for the following measured and metered values:
•
IL1dmd>: exceeding a preset maximum average value in phase L1.
•
IL2dmd>: exceeding a preset maximum average value in phase L2.
•
IL3dmd>: exceeding a preset maximum average value in phase L3.
•
I1dmd>: exceeding a preset maximum average value of the positive sequence sys-
tem currents.
•
|Pdmd|>: exceeding a preset maximum average value of the active power magni-
tude.
•
|Qdmd|>: exceeding a preset maximum average value of the reactive power mag-
nitude.
•
Sdmd>: exceeding a preset maximum average value of the apparent power.
U
L1
,U
L2
, U
L3
Voltages of the remote device Rated operat. voltage
/
√
3
2
)
U
L1
, U
L2
, U
L3
local Voltages of the local device Rated operat. voltage
/
√
3
2
)
ϕ
(U
L1
),
ϕ
(U
L2
),
ϕ
(U
L3
)
Phase angles between the remote
and the local voltages °
Tabelle 6-18 Operational measured values transmitted from the other ends and compared
with the local values
Data
% referring to
1
) for lines according to address
1104
(see Section 6.1.3)
2
) according to address 1103 (see Section 6.1.3)