Toshiba GR200 Series - 2.12.5 Protection for week infeed terminal; (i) ECHO function

6F2S1914 (0.49)
GRL200 (Soft 033 & 037)
- 195 -
≥1
8000001B78
8100001B79
8200001B7A
8300001B7B
800000EB55 DISCAR_F.BLOCK
810000EB56 DISCAR_PERMIT
≥1
1
&
&
8F00001B7C
DISCAR-S
INT.DISCAR-S-S
INT.DISCAR-S-C
INT.DISCAR-S-B
INT.DISCAR-S-A
DISCAR-CS-S_BOP
DISCAR-CS-C_BOP
DISCAR-CS-B_BOP
DISCAR-CS-A_BOP
1
&
1
&
1
&
1
&
TSCT-Dis
DISCAR-OPT-A
DISCAR-OPT-B
DISCAR-OPT-C
&
&
&
From SOTF-OC
≥1
≥1
≥1
Z1G-TRIP-A
Z1G-TRIP-B
Z1G-TRIP-C
Z1S-OPT
OCH-RETRIP
≥1
&
t 0
t 0
t 0
t 0
0.00 to 1.00s
From Z1G
BOP
Dis-CAR
used for the
external carrier communication
used for the
integral carrier communication
Figure 2.12-6 Sending circuit of BOP
2.12.5 Protection for week infeed terminal
Both POP and UOP are provided with ECHO and WIKT; both are used for a line including
weak infeed terminals.
(i) ECHO function
With regard to POP, if a terminal receives a trip permission signal when neither forward
overreaching element nor reverse looking element have operated, ECHO sends back the
received signal to the opposite terminal.
With regard to UOP, if a terminal receives a block signal when neither forward
overreaching element nor reverse looking element have operated, ECHO stops sending the
block signal to the opposite terminal.
When CB is open, ECHO sends back the trip permission signal or stops sending the trip
block signal. User can set the time from CB opened to ECHO enabled using setting
[TCARECCB].
The terminal on which the forward overreaching element has operated can issue a trip
signal speedy by using the signal by ECHO.
Once the forward overreaching element or reverse looking element have operated,
transmission of the echo signal is inhibited for 250 ms by delayed drop-off timer T1 even after
these elements are reset.
To prevent any spurious echo signal from looping round between the terminals in a