178
Calculation Formula
4. Active power (P)
Wiring
Item
Single phase
2-wire
1P2W
Single phase
3-wire
1P3W
3-phase 3-wire
3P3W2M
3-phase 3-wire
3P3W3M
3-phase 4-wire
3P4W
P [W]
P
1
P
c
=
( )
∑
−
=
×
1
0
1
M
s
cscs
IU
M
P
1
P
2
P
1
P
2
P
1
P
2
P
3
During 1P3W1U
U
2
=−U
1
P
sum
=P
1
+P
2
P
sum
=P
1
+P
2
+P
3
• The polarity symbols of active power P, indicate the current ow direction of the power during
consumption (+P), and during regeneration (−P).
c
: measurement channel,
M
: number of samples per period,
s
: number of sample points
5. Voltage DC value (Udc), Current DC value (Idc)
Wiring
Item
Single phase
2-wire
1P2W
Single phase
3-wire
1P3W
3-phase 3-wire
3P3W2M
3-phase 3-wire
3P3W3M
3-phase 4-wire
3P4W
Udc [V]
Udc
1
Udc
4
Udc
c
=
∑
−
=
1
0
1
M
s
cs
U
M
Udc
1
Udc
2
Udc
4
Udc
1
Udc
2
Udc
3
(U
3S
=U
2S
−U
1S
)
Udc
4
Udc
12
=
( )
∑
−
=
−
1
0
2
21
1
M
s
ss
UU
M
Udc
23
=
( )
∑
−
=
−
1
0
2
32
1
M
s
ss
UU
M
Udc
31
=
( )
∑
−
=
−
1
0
2
13
1
M
s
ss
UU
M
Udc
1
Udc
2
Udc
3
Udc
4
During 1P3W1U
Without
Udc
2
During 3P4W2.5E
U
3
(U
3S
=U
1S
−U
2S
)
(
U
1S
+U
2S
+U
3S
= 0
is
the assumption)
Idc [A]
Idc
1
Idc
4
Idc
c
=
∑
−
=
1
0
1
M
s
cs
I
M
Idc
1
Idc
2
Idc
4
Idc
1
Idc
2
Idc
3
(I
3S
=−I
1S
−I
2S
)
Idc
4
Idc
1
Idc
2
Idc
3
Idc
4
c
: Measurement channel,
M
: Number of samples per period,
s
: Number of sample points