Toshiba GRL100-701B Instruction Manual page 23

time difference between send and receive terminals is less than the PDTD setting and the SYNC
ALARM LED is off. If these conditions are not satisfied, the operation may cause a false
tripping.
Note: The mode change with the binary input signal is performed by either way:
• If the binary input contact is such as to be open when the relay is in service, set
the BI to "Inv" (inverted). The mode changes when the contact is closed more
than 2 seconds and then open.
• If the binary input contact is such as to be closed when the relay is in service, set
the BI to "Norm" (normal). The mode changes when the contact is open more
than 2 seconds and then closed.
For the BISW4, see Section 3.2.1.
In the three-terminal application, the mode change to Mode 2B is available even
when one of the three communication routes is failed.
Mode 2B: The same intra-system synchronization as in Mode 2A is applied.
When the GPS signal has been restored, the mode shifts from Mode 2B to Mode 0.
If a failure occurs in the communication system, the sampling timing adjustment is disabled and
each terminal runs free.
The mode shifts from Mode 2B to Mode 2A, when the apparent load current phase difference
exceeds the value determined by the PDTD setting for pre-determined time.
Checking the current phase difference (For two-terminal application setting only)
The current phase difference is checked using the following equations:
⋅ cos θ < 0
I
1A
⋅ I sin θ < I ⋅ I
I
1A 1B 1A
I > OCCHK
1A
I > OCCHK
1B
Where,
I = Positive sequence component of load current at local terminal
1A
I = Positive sequence component of load current at remote terminal
1B
θ
= Phase difference of I
θs = Critical phase difference
= CHKθ‐HYSθ
PDTD(µs)
CHKθ =
2
HYSθ = Margin of phase difference checking
OCCHK = Minimum current for phase difference check
If the magnitude of I and I
1A
established, then the sampling is regarded to be synchronized.
If the current phase difference exceeds a set value, the "SYNC ALARM" LED on the front panel
is lit.
Checking the current phase difference is enabled by setting the scheme switches [TERM] to
"2TERM" and [SRCθ] to "I".
sin θs
1B
from - I
1B 1A
360°
×
+ 8.5°
20000(µs)
exceed the setting and the conditions for both equations above are
1B
 22 
6 F 2 S 0 8 5 0