Functions
6-123
7SA6 Manual
C53000-G1176-C156-2
suited for a highly-sensitive earth fault detection. A fourth, definite time stage can be
implemented by setting the “inverse” stage (refer to the next paragraph) to a definite
time stage.
Inverse Time
Overcurrent
Stage 3I
0P
The logic of the inverse time stage in principle functions the same as the other stages.
This stage operates with a specially optimized digital filter that completely suppresses
all harmonic components beginning with the 2nd harmonic. Therefore it is particularly
suited for a very sensitive earth fault detection. The delay times in this case are how-
ever determined by the set characteristic (Parameter
IEC Curve
), the magnitude of
the earth current and the time multiplier
3I0p Time Dial
(Figure 6-70). A pre-se-
lection of the optional characteristics was already done during the configuration of the
protection functions. Furthermore, an additional fixed delay
Add.T-DELAY
may be
selected. The optional characteristics are illustrated in the technical data of Section
10.5.
Figure 6-70 shows the logic diagram. As an example, the setting addresses for the IEC
curves are shown in the diagram. The different setting addresses are referred to in
more detail in the setting information (Sub-section 6.7.2)
It is also possible to implement this stage as a further definite time stage. In this case
3I0p PICKUP
is the pick up threshold and
Add.T-DELAY
the definite time delay. The
inverse time characteristic is then effectively bypassed.
Figure 6-70
Logic diagram of the 3I
0P
–stage (inverse time overcurrent protection), for example IEC curves
Inverse Time
Overcurrent Stage
with Inverse
Logarithmic
Characteristic
The inverse logarithmic characteristic differs from the other inverse characteristics
mainly by the fact that the shape of the curve can be influenced by a number of pa-
rameters. The slope
3I0p Time Dial
and a time shift
T I0Pmax
which directly af-
fect the curve, can be changed. The curves are illustrated in the technical date in Sec-
tion 10.5, Figure 10-4.
I
E
3I
0P
3141
Yes
No
Reverse
Forward
Non-Directional
„1“
≥
1
&
&
inrush
stabilization
direction
determination
forwards
reverse
&
&
Yes
No
3I0p SOTF-Trip
3148
Yes
No
3I0p Telep/BI
permissive
teleprot.
switch on
to fault
≥
1
EF 3I0p TRIP
T
0
3173
SOTF Time DELAY
&
&
PICKUP
DIRECT.
3172
&
SOTF Op. Mode
t
3I
0
3143
T
0
3151
3140
1309 >EF BLOCK 3I0p
3149
1357 EF 3I0p Pickup
1369
3150
3147
≥
1
>EF Inst TRIP
Add.T-DELAY
IEC Curve
3I0p PICKUP
Op. mode 3I0p
3I0p InrushBlk
3I0p Time Dial
Inactive
FNo1310
Содержание siprotec 7SA6
Страница 2: ...Siemens Aktiengesellschaft Book No C53000 G1176 C156 2 ...
Страница 18: ...xviii 7SA6 Manual C53000 G1176 C156 2 ...
Страница 32: ...Introduction 1 14 7SA6 Manual C53000 G1176 C156 2 ...
Страница 82: ...Hardware and Connections 2 50 7SA6 Manual C53000 G1176 C156 2 ...
Страница 119: ...SIPROTEC 4 Devices 4 25 7SA6 Manual C53000 G1176 C156 2 Figure 4 20 CFC Logic example ...
Страница 190: ...Configuration 5 62 7SA6 Manual C53000 G1176 C156 2 ...
Страница 559: ...Control During Operation 7 45 7SA6 Manual C53000 G1176 C156 2 Figure 7 45 Circuit breaker trip test in DIGSI 4 ...
Страница 652: ...Installation and Commissioning 8 78 7SA6 Manual C53000 G1176 C156 2 ...
Страница 724: ...Technical Data 10 56 7SA6 Manual C53000 G1176 C156 ...
Страница 800: ...Appendix A 76 7SA6 Manual C53000 G1176 C156 2 ...
Страница 866: ...Appendix B 66 7SA6 Manual C53000 G1176 C156 2 ...