Hioki CM3286-50, Instruction Manual

Page: 101 / 118

95
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)
) 4 3 (
) 4 3 (
W P
W P
S
P
(4) Unbalanced 3‑phase/3‑wire power measurement
Unbalanced 3‑phase/3‑
wire active power
P
(UB3P3W)
[W]
P1 + P2
• The symbol
P1
represents the active power of
the line voltage U
21
and the wire current 1
1
.
• The symbol
P2
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.
HIOKI CM3286C961-00