Siemens siprotec 7SA6, Manual

Page: 259 / 876

Functions
6-69
7SA6 Manual
C53000-G1176-C156-2
Figure 6-37 Tripping logic for the 4th and 5th Zone, shown is zone Z4
Zone Logic
of the Controlled
Zone Z1B The controlled zone Z1B is usually applied as an overreaching zone. The logic is
shown in Figure 6-38. It may be activated via various internal and external functions.
The binary inputs for external activation are “
>ENABLE Z1B
” and “
>Enable AR-
zones
”. The former can for example be from an external teleprotection device, and
only affects Z1B of the distance protection. The latter affects all protection functions
that include a rapid auto-reclosure stage; it may for example be derived from an exter-
nal automatic reclose device. In addition, it is possible to use the zone Z1B as a rapid
auto-reclosure stage that only operates for single-pole faults, if for example only sin-
gle-pole automatic reclose cycles are executed.
It is possible for the 7SA6 to trip single-pole during two-phase faults without earth-con-
nection in the overreaching zone when single-pole automatic reclosure is used.
As the device has an integrated teleprotection function (refer to Section 6.6), release
signals from this function may activate the zone Z1B, provided that the internal tele-
protection signal transmission function has been configured to one of the available
techniques with parameter
121 Teleprot. Dist.,
i.o.w. the function has not
been set to
Disabled.
Dis FD Z4 L3
Dis FD Z4 L2
Dis FD Z4 L1
≥
1
T 0
≥
1
&
Tripping logic
of the distance
protection
&
Dis bl Z4 trip
Z4 undelayed
(refer Fig. 6-28)
3801 Dis G–trip
3778 Dis T4 exp.
3805 Dis trip L123
3821 Dis trip Z4
1335 T4 DELAY
FNo 3617