Blocking Scheme - Siemens siprotec 7SA6 User Manual

FNr 4032
1-L1
>Dis.T.UB
FNr 4033
1-L2
>Dis.T.UB
FNr 4034
1-L3
>Dis.T.UB
FNr 4030
ub 1
>Dis.T.UB
FNr 4031
bl 1
>Dis.T.UB
FNr 4035
ub 2
>Dis.T.UB
FNr 4032
bl 2
>Dis.T.UB
Figure 6-53 Unblock–logic
6.4.1.7

Blocking scheme

Principle
7SA6 Manual
C53000-G1176-C133-1
&
20
&
&
20
&
&
≥1
20
&
&
20
&
&
20
&
The blocking scheme uses the transmission channel to send a block signal from one
line end to the other. The signal is sent as soon as the protection function has detected
a fault in reverse direction, optionally also directly after fault inception (jump detector
via the dashed line in Figure 6-54). It is stopped, as soon as the distance protection
detects a fault in the forward direction, alternatively the signal is only sent when the
distance protection detects the fault in the reverse direction. The signal will be
maintained if the fault is in reverse direction. If the signal is sent with jump detection
(i.e.  'LV-XPS%ORFNLQJ routed in parallel with  -  ) only a short delay
to allow for signal transmission is required before Z1b trips. A trip can be achieved with
≥1
0 100 100
ms ms
10 0
s
≥1
0 100 100
ms ms
10 0
s
≥1
0 100 100
ms ms
10 0
s
≥1
0 100 100
ms ms
10 0
s
≥1
0 100 100
ms ms
10 0
s
&
&
&
&
≥1
&
Functions
Unblock L1
Unblock L2
Unblock L3
Unblock 1
FNr 4080
Dis.T.UB Fail1
Unblock 2
FNr 4081
Dis.T.UB Fail1
6-89