Panasonic KW8M User Manual page 15

◆When measuring a load with exceed input voltage
Voltage transformer (VT) is needed when you measure a load with over rated input voltage (440V).
Use a VT, those secondary rating is 110V.
Grounding the secondary side of VT and CT is not necessary with low-voltage circuit.
Single-phase two-wire system
VT
11
12
13
14
15
16
Back View
No.13, 14, 17, 18, 19, 20 are not wired.
Three-phase, three-wire system
VT
P1
11
P0
12
P2
13
14
k
15
16
17
18
Back View
No.14, 19, 20 are not wired.
L N
P1
P0
k
CT1
l
R S
CT1
k
CT2
KW8M Eco-POWER METER (1A/5ACT input type)
Single-phase, three-wire
P1
11
P0
12
P2
13
14
15
16
17
18
Back View
No.14, 19, 20 are not wired.
Three-phase, four-wire system
T
11
12
13
14
15
16
17
18
19
20
Back View
7
VT R
k
CT1
l
k
l
VT
R
P1
P0
P2
P3
k
CT1
l
k
l
k
l
N S
CT2
S T N
CT2
CT3