Siemens siprotec 7SA6 User Manual

Functions
6-1057SA6 Manual
C53000-G1176-C133-1
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
parameters. The slope ,S7LPH'LDO and a time shift 7 ,3PD[ which directly
affect the curve, can be changed. The curves are illustrated in the technical date in
Section 10.5, Figure 10-4.
The logic diagram is shown in Figure 6-63. In addition to the curve parameters, a
minimum time ,S0LQ7'(/$< can be determined; below this time no tripping can
occur. Below a current factor of ,S6WDUWSRLQW, which is set as a multiple of the
basic setting ,S3,&.83, no tripping can take place.
Further information regarding the effect of the various parameters can be found in the
setting information of the function parameters in Sub-section 6.5.2, refer also to Figure
6-68.
The remaining setting options are the same as for the other curves.
Figure 6-63 Logic diagram of the 3I
0P
–stage for the inverse logarithmic curve
Zero Sequence
Voltage Time
Protection
(U
0
-Inverse)
The zero sequence voltage time protection operates according to a voltage-
dependent trip time characteristic. It can be used instead of an inverse time
overcurrent stage.
The voltage/time characteristic can be displaced in voltage direction for a determined
constant voltage (8LQYPLQLPXP, valid for t → ∞) and in time direction by a
determined constant time (7IRUZ8LQY). The different characteristics and their
underlying formulae are shown in the Technical Data Section (10.5, Figure 10-5).

Yes
No
Reverse
Forward
Non-Directional
„1“
≥1
&
&
inrush-
stabilization
direction-
determination
forwards
reverse
&
&
Yes
No

Yes
No
,S7HOHS%,
permissive
teleprot..
switch on
to fault
≥1
T0
 627)7LPH'(/$<
&
&
PICKUP
PICKUP+DIRECT.

&
627)2S0RGH
I
E
3I
0P


t
3I
0

T0
 /2*&XUYH

&

T0

1309
>EF BLOCK 3I0p
,S,QUXVK%ON
1357
EF 3I0p Pickup
,S627)7ULS

EF 3I0p TRIP
1369
,S6WDUWSRLQW

≥1
>EF Inst TRIP
,S3,&.83
2SPRGH,S
$GG7'(/$<
,S0LQ7'(/$<
Inactive
,S0D[7'(/$<
,S7LPH'LDO
FNo 1310

Siemens siprotec 7SA6 Specifications

General

Brand	Siemens
Model	siprotec 7SA6
Category	Relays
Language	English