Toshiba GR200 Series Instruction Manual page 500

VCHK1 and VCHK2 for 1.5CB system
2.35.2
Characteristic and elements
(i)
VCHK1 and VCHK2 are used for verification of existence or non-existence of voltage on 1.5CB
system. As shown in Figure 2.35-3(b), VCHK2 is used in the center CB (CB#2). Four elements
(OVL2, UVL2, OVL, and UVL) are configured for VCHK2; they are used for determination of
existence or non-existence of voltage.
Voltage condition and check zone
(ii)
Figure 2.35-3(a) shows that VCHK1 checks the presence of voltage between the Bus-bar and
Line; Figure 2.35-3(b) shows that the VCHK2 checks the presence of voltage between Line2
and Line. The result of the VCHK1 and VCHK2 are shown in Table 2.35-3 and Table 2.35-4,
respectively. Sync check is carried out if the result by VCHK1 is B1 zone and if the result by
VCHK2 is B2 zone.
V L Line voltage
(Incoming voltage)
Dead bus and
live line
A1
(DB-LL)
VCHK-OVL
Dead bus and
dead line
(DB-DL)
VCHK-UVL
C1
VCHK-UVB
0 (V)
A1, C1, D1:
a. VCHK1 check zone
B1:
Voltage condition
Bus-bar voltage (V B )
Line voltage (V L )
Voltage condition
Check zone
Line2 voltage (V L2 )
Line voltage (V L )
Live bus and
live line
B1
(LB-LL)
Live bus and
dead line
(LB-DL)
D1
V Bus-bar voltage
B
VCHK-OVB
(Running voltage)
Voltage check
Synchronism check
Figure 2.35-3 Check zones by VCHK1 and VCHK2
Table 2.35-3 Voltage condition by VCHK1
DB_LL
Check zone
Dead
Table 2.35-4 Voltage condition by VCHK2
DL2_LL
A2
Dead
Live
V L Line voltage
(Incoming voltage)
A2
VCHK-OVL
VCHK-UVL
C2
VCHK-UVL2
0 (V)
b. VCHK2 check zone
LB_LL DB_DL
A1 B1
Live Dead
Live Live Dead
LL2_LL DL2_DL
B2 C2
Live Dead
Live Dead
- 477 -
6F2S1914 (0.49)
Live line and
dead line2
B2
(DL2-LL)
Dead line and
dead line2
(DL2-DL)
D2
VCHK-OVL2
A2, C2, D2:
B2:
LB_DL
C1 D1
Live
Dead
DL2_LL
D2
Dead
Live
GRL200 (Soft 033 & 037)
Live line and
live line2
(LL2-LL)
Dead line and
Live line2
(LL2-DL)
V L2 Line2 voltage
(Running voltage)
Voltage check
Synchronism check