Toshiba GRL100-101A, Инструкция по эксплуатации

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⎯
30
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6 F 2 S 0 8 3 5
necessary to check whether any fault causes CT saturation, particularly in the terminal with
outflow, and the saturation must be accommodated utilising the DIFI2 setting of the DIF
element.
2.2.11 Dual Communication Mode
Three-terminal application models have dual communication mode (GRL100-
∗
1
∗
). By
connecting the remote terminal with dual communication routes, even if one of the routes fails, it
is possible to continue sampling synchronization and protection by the current differential relay.
To set dual communication mode, select "Dual" in the TERM setting. Other settings are the same
as that of the two-terminal. In GPS-MODE setting, however, the dual communication mode
cannot be applied.
GRL100
GRL100
CH1
CH2
CH1
CH2
Figure 2.2.11.1 Dual Communication Mode
2.2.12 Application to One-and-a-half Breaker Busbar System
The GRL100 models 301, 311, 302, 501, 511, 503, 513, and 513 are used for lines connected via
a one-and-a-half breaker busbar system, and have functions to protect against stub faults and
through fault currents.
Stub fault
If a fault occurs at F1 or F2 when line disconnector DS of terminal A is open as shown in Figure
2.2.12.1, the differential protection operates and trips the breakers at both terminals.
Terminal A
F2 F1
DS
× × ×
Terminal B
× × ×
Figure 2.2.12.1 Stub Fault
A scheme switch [STUB] and stub fault detection logic as shown in Figure 2.2.12.2 are provided
to avoid unnecessary trippings of the breakers in these cases.
DS
&
[STUB]
STUB ON
"ON"
(
+
)
1
Figure 2.2.12.2 Measure for Stub Fault
If the switch is set to "ON" and the disconnector is open (DS = 0), the signal STUB ON is