Toshiba GR200 Series - (vi) CT polarity settings

6F2S1914 (0.49)
GRL200 (Soft 033 & 037)
- 1037 -
IED
I
a
DIF function
Setting [APPL-CTSELECT] = 2CT
Busbar
Three-phase
currents
A
C
B
VCT
CT
I
a
I
b
I
c
Feeder#1
I
b
I
c
Feeder#2
Busbar
CB#2
CB
CB#1
I
a2
I
b2
I
c2
1CT
2CT
Figure 5.2-14 1.5CB arrangement with [APPL-CTSELECT]=2CT
(vi) CT polarity settings
The user can reverse the CT polarity using settings. For example, the user wishes to change
the polarity to negative in the first currents group (that is, Ia, Ib, and Ic on the VCT; we term
them ‘1CT’), set Negative for the setting [Pol-1CT]. Similarly, for the second current group
(that is, Ia2, Ib2, and Ic2), set Negative for the setting [Pol-2CT]. The user can also change the
polarity in ‘Ie’, ‘Ie2’, ‘Iem’, as shown in Table 5.2-1.
Setting [Pol-1CT] = Positive
Busbar
1CT
VCT
CT
I
a
I
b
I
c
Line1
CB#2
CB
CB#1
I
e
1CT-Ie
Busbar
Line2
I
em
CT-Iem
Setting [Pol-1CT-Ie] = Positive
Setting [Pol-CT-Iem] = Positive
Figure 5.2-15 Positive settings for Paralleling connected CTs in VCT12B