Step 1 – Connection of CTs
Remove all interposing CTs from the secondary circuit. Connect all line CT secondary wiring in star.
45
HV load current =
3
132,000
45
LV load current =
3
33,000
Step 2 – Selection of Interposing CT Multiplier Settings
196.8
HV Secondary current =
LV Secondary current =
560
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6
10
A
196
8 .
6
10
A
. 0
95
747
9 .
. 0
66
A
00
3
747.9
. 0
77
A
/
. 0
577
Figure 2-13 Summary of ICT Settings
Re-use 300/1A CTs.
Re-use 560/0.577A CTs.
HV ICT Multiplier = 1/0.66 = 1.54
LV ICT Multiplier = 1/0.77 = 1.30
Chapter 7 Page 23 of 64