Toshiba GR200 Series - (ii)-2 Example2

6F2S1914 (0.49)
GRL200 (Soft 033 & 037)
- 1292 -
or if the connections between the trip circuit and the BI circuits become open circuit, a signal
"TC1_FAIL" is generated; then, the TCS1 logic will issue a Trip Circuit Fail alarm.
Note: A threshold setting voltage is required for the BI circuits. The user should set the
threshold to one-half of the value of the trip supply voltage. This is because in this
scheme there are two BI circuits connected in series. The supply voltage across the
BI circuit will be divided by two when the 52 contact is closed and the 52b contact
is open. Thus, the BI circuit may fail to operate if the BI sensitivity is only set in
response to the supply voltage. For example, the BI threshold voltage should be
set below 55V when a trip supply voltage of 110V is applied. For the TCS function,
the user should select two BI circuits from the BI2A module, because the BI
circuits of both of these modules can have lower threshold voltages than the BI
circuits that are available in other modules.
Trip coil
52a
52b
Protection
relay
Trip circuit
( + )
( − )
LCP & GIS
1
BI1
BI2
1
≥1
TCS1-EN
OPT-On
&
On
&
Binary input
circuit
Binary input
circuit
t
0
0.4s
0
t
0.4s
TC1_FAIL
TC1_FAIL_COND
800001EBB2
8000011BB0
8000011BB1
8000011BB2
8000011B60
TC1_FAIL_SIGNAL1
800001EBB0
TC1_FAIL_SIGNAL2
800001EBB1
R
R
Figure 10.3-2 Connection Example1 for TCS1 logic
Example2
In Example2 a binary input signal is assigned to PLC connection point “TC1_FAIL_SIGNAL1”.
With this arrangement if the CB is open, the small monitoring current will not be able to flow
in the BI circuit. Therefore, it is recommended that setting OPT-On is selected for the scheme
switch [TCS1-EN] and that a CB-closed-status signal is applied to PLC connection point
“TC1_FAIL_COND”. Monitoring is only enabled while the CB is in the closed position when
using this setting. This setting avoids unnecessary monitoring when the circuit breaker is open
when using this scheme.