91
9. Appendix
9.2. A List of Examples for Incorrect Wiring Display
9.2.2. 3-phase 3-wire System
Note1: When 1 side CT and 3 side CT switch to each other, and in addition, the terminals
‘C3’ and ‘+C3’ of CT are
connected to the terminals
‘+C1’ and ‘C1’ of the instrument in that order.
Note2: When 1 side CT and 3 side CT switch to each other, and in addition, the terminals
‘C1’ and ‘+C1’ of CT are
connected to the terminals
‘+C3’ and ‘C3’ of the instrument in that order.
Note3: When the terminals
‘C1’ and ‘+C1’ of CT are connected to the terminals ‘+C1’ and ‘C1’ of the instrument in that
order.
Note4: When the terminals
‘C3’ and ‘+C3’ of CT are connected to the terminals ‘+C3’ and ‘C3’ of the instrument in that
order.
Note5: When
‘+C1’ and ‘C3’of CT are connected and it is connected to the ‘+C1’ terminal of the instrument.
Note6: When
‘C1’ and ‘+C3’of CT are connected and it is connected to the ‘+C3’ terminal of the instrument.
Note7: The above examples for incorrect wiring are typical. Extreme cases are excluded such as burnout or destruction of
the instrument, VT, or CT caused by voltage application to a current circuit or current application to a voltage circuit.
Note8: The active power polarity may be displayed in reverse depending on the load status (low power factor, unbalanced
load) even if the connection is correct.
Note9: The above table shows incorrect wiring display examples of 3-phase 3-wire system (2CT). Those of 3-phase 3-wire
system (3CT) are also the same. However, it is not possible to detect the incorrect wiring of the CT secondary side.
∠
V
12
∠
V
32
∠
I
1
∠
I
3
W
1
W
3
V
12
V
23
V
31
I
1
I
2
I
3
1
2
3 1 side CT 3 side CT
30
LEAD 0.707
45 105
LEAD 0.866
60 120
1.000
90 150
LAG 0.866
120 180
LAG 0.707
135 195
31
LEAD 0.707
225 285
LEAD 0.866
240 300
1.000
270 330
LAG 0.866
300
0
LAG 0.707
315
15
32
LEAD 0.707
285 345
LEAD 0.866
300
0
1.000
330
30
LAG 0.866
0
60
LAG 0.707
15
75
33
LEAD 0.707
105 165
LEAD 0.866
120 180
1.000
150 210
LAG 0.866
180 240
LAG 0.707
195 255
+C3-C3
Reverse
W
1
=Negative value
W
3
=0
W
1
=Negative value
W
3
=Positive value
0
300
W
1
=Negative value
W
3
=Negative value
V
12
=V
23
=V
31
I
1
=I
3
＜
I
2
P2
0
300
W
1
<W
3
V
12
=V
23
=V
31
I
1
=I
3
＜
I
2
P2
P3
P1
+C1-C1
Normal
W
1
=0
W
3
=Negative value
W
1
=Negative value
W
3
=Negative value
P3
P1
+C1-C1
Reverse
+C3-C3
Normal
W
1
=W
3
W
1
=Positive value
W
3
=0
W
1
=Positive value
W
3
=Negative value
0
300
W
1
=Negative value
W
3
=Positive value
V
12
=V
23
=V
31
I
1
=I
3
＜
I
2
P3
P1
Connection
0
300
W
1
=Positive value
W
3
=Negative value
V
12
=V
23
=V
31
I
1
=I
3
＜
I
2
P3
P1
P2
+C1-C1
Reverse
P2
+C1-C1
Normal
+C3-C3
Reverse
W
1
=0
W
3
=Positive value
W
1
=W
3
W
1
>W
3
+C3-C3
Normal
No.
Power Factor
(Input)
At balanced load (V
12
=V
23
, I
1
=I
3
)
Connection (*7)
Phase Angle Display Active Power Display
Voltage Display
Current Display
Voltage
Current
+C2
C2
+C3
C3
P1
P3
NC
+C1
C1
P2
K
L
k
l
K
L
k
l
U
u
V
v
U
u
V
v
1
2
3
+C2
C2
+C3
C3
P1
P3
NC
+C1
C1
P2
K
L
k
l
K
L
k
l
U
u
V
v
U
u
V
v
1
2
3
+C2
C2
+C3
C3
P1
P3
NC
+C1
C1
P2
K
L
k
l
K
L
k
l
U
u
V
v
U
u
V
v
1
2
3
+C2
C2
+C3
C3
P1
P3
NC
+C1
C1
P2
K
L
k
l
K
L
k
l
U
u
V
v
U
u
V
v
1
2
3
