APPENDIXE:CALCULATIONS&EQUATIONS
Measuringcentres
MC320,MC330,MC350&MC350H ‐ User’sManua
73
Current
N
=
i
I
2
n
N
1=n
RMS
Phasecurrent
N‐128samplesinaperiod(upto65Hz)
N‐128samplesinmoreperiods(above65Hz)
N
iii
=
2
n3n2n1
N
1=n
n
I
Neutralcurrent
i‐nsampleofphasecurrent(1,2or3)
N‐128samplesinaperiod(upto65Hz)
Power
N
1n
fnfnf
iu
N
1
P
Activepowerbyphases
N‐anumberofperiods
n‐indexofsampleinaperiod
f‐phasedesignation
321t
PPPP
Totalactivepower
t‐totalpower
1,2,3‐phasedesignation
1360801
11800
f
f
f
SignQ
SignQ
SignQ
Reactivepowersign
Q
f
‐reactivepower(byphases)
φ‐powerangle
fff
IUS
Apparentpowerbyphases
U
f
‐phasevoltage
I
‐phasecurrent
321t
SSSS
Totalapparentpower
S
f
‐apparentpowerbyphases
2
f
2
fff
PSSignQQ
Reactivepowerbyphases
S
f
‐apparentpowerbyphases
P
f
‐activepowerbyphases
321t
QQQQ
Totalreactivepower
Q
‐reactivepowerbyphases
99,179,180
,2arctan
s
tts
QP
Totalpowerangle
P
t
‐totalactivepower
S
t
‐totalapparentpower
t
t
t
S
P
PF
3phasepowerfactor
P
t
‐phaseactivepower
S
t
‐phaseapparentpower
f
f
f
S
P
PF
Powerfactorbyphases
P
f
‐phaseactivepower
S
‐phaseapparentpower