Toshiba GR200 Series Instruction Manual page 931

Settings for residual voltage, CT polarity, and busbar arrangements
5.2.5
In the IED, the residual voltage represented 'Ve' is given by the computation with three-phase
voltages (V a , V b , and V c ), but the VCT is ready to obtain it exclusively using APPL-VCT
settings when the residual voltage transformer is connected with the VCT. Additionally, the
VCT has the settings for changing the CT polarity so that the user can reverse the polarity
without wiring works.
Setting [APPL-Ves2] = Ve
(i)
Set Ve for the setting [APPL-VTes2], when the residual voltage transform is provided. Figure
5.2-8 illustrates the signals from the VTs on the feeder are injected for the 'Ve' terminal on the
VCT.
CB#1
A B C
Feeder
Setting [APPL-Ves2]=Ve
Setting [APPL-Ves2] = Vs2
(ii)
Figure 5.2-9 illustrates the residual voltage transform is not provided; set Vs2 for the setting
[APPL-VTes2]. Note that the IED computes the voltage in zero-sequence mathematically (3V0)
using the three-phase voltages.
APPL-VCT
10:48
APPL-Ves2
Vs2
Polarity Change
Figure 5.2-7 APPL-VCT setting screen
VT on busbar
VTs on feeder
Figure 5.2-8 Connection with residual VT
- 910 -
1/2
+
>
Busbar
IED
VCHK function
VCT
Three-phase voltages
VT
Va
V L1
Vb
V L2
Vc
V L3
Reference voltage
V s V3
Residual voltage
Ve (V0)
V s2 /V e
6F2S1915 (0.46)
GRZ200 (Soft 031 & 032)