Siemens 7SJ82, Руководство пользователя

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Blocking the Stage
In the event of blocking, the picked up stage will be reset. Blocking is possible externally or internally via the
binary input signal
>Block stage
.
Application and Setting Notes
Parameter:
Method of measurement
•
Recommended setting value
(_:8) Method of measurement
=
fundamental comp.
With the
Method of measurement
parameter, you define whether the tripping stage uses the fundamental
component (standard method = default setting) or the calculated RMS value.
Parameter Value Description
fundamental comp.
Select this method of measurement to suppress harmonics or transient
voltage peaks.
Siemens recommends this method of measurement as the default setting.
RMS value
Select this method of measurement if you want the stage to take harmonics
into account (for example, at capacitor banks). Do not set the threshold
value of the tripping stage under 10 V for this method of measurement.
Parameter:
Measured value
•
Default setting
(_:9) Measured value
=
phase-to-phase
With the
Measured value
parameter, you define whether the tripping stage monitors the phase-to-phase
voltages V
AB
, V
BC
, and V
CA
or the phase-to-ground voltages V
A
, V
B
, and V
C
.
Parameter Value Description
phase-to-phase
If you want to monitor the voltage range, keep
phase-to-phase
as the
default setting. In this case, the function will not pick up on ground faults.
Siemens recommends the measured value
phase-to-phase
as the
default setting.
phase-to-ground
Select the
phase-to-ground
setting if you want to detect voltage unbal-
ances and overvoltage conditions caused by ground faults.
Parameter:
Threshold
,
Pickup factor
•
Default setting
(_:3) Threshold
=
110.000 V
•
Default setting
(_:101) Pickup factor
=
1.10
The stage picks up when the measured voltage value exceeds the pickup value
Threshold
×
Pickup
factor
.
Depending on the
Measured value
, the
Threshold
is set either as phase-to-phase quantity or as phase-to-
ground quantity.
With the
Pickup factor
parameter, you modify the pickup value. To avoid a long-time operate delay after
pickup when the measured value is slightly over the threshold, Siemens recommends using the default
setting.
Specify the
Threshold
(pickup threshold) and
Pickup factor
for the specific application.
Parameter:
Pickup mode
•
Recommended setting value
(_:182:101) Pickup mode
=
1 out of 3
With the
Pickup mode
parameter, you define whether the protection stage picks up if all 3 measuring
elements detect the overvoltage condition (
3 out of 3
) or if only 1 measuring element detects the over-
voltage condition (
1 out of 3
).
6.23.4.2
Protection and Automation Functions
6.23 Overvoltage Protection with 3-Phase Voltage
SIPROTEC 5, Overcurrent Protection, Manual 701
C53000-G5040-C017-8, Edition 07.2017