Hioki CM3286 - Page 94

88
Equations
(3) Balanced 3-phase/4-wire power measurement
Balanced 3-phase/4-wire
active power
P
(3P4W)
[W]
3
・
P
• The symbol
P
represents the active power of
the phase voltage
U
1
and the wire current
I
1
.
• The symbol
S
represents the apparent power of
the phase voltage
U
1
and the wire current
I
1
.
• The symbol
Q
represents the reactive power of
the phase voltage
U
1
and the wire current
I
1
.
• The active power
P
has no sign during
consumption and a negative sign during
generation.
• Due to the effects of measurement error
,
S
=|
P
|
and
Q
=0 are used when
S
<|
P
|.
Balanced 3-phase/4-wire
apparent power
S
(3P4W)
[VA]
3
・
S
Balanced 3-phase/4-wire
reactive power
Q
(3P4W)
[var]
3
・
Q
Balanced 3-phase/4-wire
power factor
PF
(3P4W)
)43(
)43(
WP
WP
S
P
(4) Unbalanced 3-phase/3-wire power measurement
Unbalanced 3-phase/3-wire
active power
P
(UB3P3W)
[W]
P
1
+
P
2
• The symbol
P
1
represents the active power of
the line voltage
U
21
and the wire current
1
1
.
• The symbol
P
2
represents the active power of
the line voltage
U
23
and the wire current
1
3
.
• The active power
P
has no sign during
consumption and a negative sign during
generation.