Figure - Toshiba GR200 Series Instruction Manual

Delay of trip permission signal
(vi)
Figure 2.3-4 shows POP sending circuit. The trip permission signals are (DISCAR-S: used for
the external carrier communication) and (INT.DISCAR-S-*: used for the integral carrier
communication). The selection of either the single-phase trip (1P) or the three-phase trip (3P)
is carried out using scheme switch [DisCAR-TPMD].
Transmission of the trip permission signal continues for setting [TSBCT-dis] even after
the local terminal issues a trip signal.
In many cases, at both ends of the line, the overreaching elements operate at the same
time. However, there may be some cases where they cannot operate simultaneously because
fault currents do not flow symmetrically. That is, the overreaching elements far from a fault
cannot operate by the fault, but the overreaching elements far from the fault will be operated
indirectly if the other terminals are induced to trip. To avoid this case, transmission of the trip
permission signal continues for a while set by [TSBCT-dis] after reset of ZCSF/ZCSG operation.
Consequently, the overreaching elements far from the fault can also generate a trip signal
because the trip permission signal is picked up delayed.
Thus, this command protection ensures its operation at the remote terminal.
DISCAR-OPT-A
DISCAR-OPT-B
DISCAR-OPT-C
&
From Z1G
Z1G-TRIP-A
Z1G-TRIP-B
Z1G-TRIP-C
Z1S-OPT
From SOTF-OC
OCH-RETRIP
DISCAR-CS-A_POUP
DISCAR-CS-B_POUP
DISCAR-CS-C_POUP
DISCAR-CS-S_POUP
ECHO logic
800000EB55 DISCAR_F.BLOCK
810000EB56 DISCAR_PERMIT
POP
Dis-CAR
UOP
Figure 2.3-4 Sending circuit in POP and UOP
Unblocking overreach protection (UOP)
2.3.3
When information are exchanged using a transmission line (the power line carrier), PUP and
POP cannot trip dependably. This is because a trip permission signal may not be exchanged
TSBCT-DIS
t 0
≥1
t 0
≥1
t 0
≥1
t 0
≥1
0.00 to 1.00s
≥1
≥1
≥1
≥1
≥1
- 126 -
=1
=1
=1
=1
&
≥1
&
1
≥1
& &
1
6F2S1915 (0.46)
8000001B78
INT.DISCAR-S-A
8100001B79
INT.DISCAR-S-B
8200001B7A
INT.DISCAR-S-C
8300001B7B
INT.DISCAR-S-S
used for the
integral carrier
communication
8F00001B7C
≥1
DISCAR-S
used for the
external carrier
communication
GRZ200 (Soft 031 & 032)