Alstom iSTAT M232 - Page 69

M2x2/EN M/F User Manual
iSTAT M2x2 Page 67

N
iii
=
2
n3n2n1
N
1=n
n
I


Neutral current
i − n sample of phase current (1, 2 or 3)
N = 128 samples in a period (up to 65 Hz)
Power



N
fnfnf
iu
1
P
1n
N
Active power by phases
N − a number of periods
n − a number of samples in a period
f − phase designation
321t
PPPP 
Total active power
t − total power
1, 2, 3 − phase designation





1SignQ360801
1SignQ1800
SignQ
f
f
f



Reactive power sign
Q
f
− reactive power (by phases)
φ − power angle
fff
IUS 
Apparent power by phases
U
f
− phase voltage
I
f
− phase current
321t
SSSS 
Total apparent power
S
123
− apparent power by phases

22
PSSignQQ 
ffff
Reactive power by phases
S
f
− apparent power by phases
P
f
− active power by phases
321t
QQQQ 
Total reactive power
Q
f
− reactive power by phases

 

99,179,180
Q,P2tana
s
tts
Total power angle
P
t
− total active power
S
t
− total apparent power
t
t
t
S
P
PF 
3 phase power factor
P
t
− total active power
S
t
− total apparent power
f
f
f
S
P
PF 
Power factor by phases
P
f
− phase active power
S
f
− phase apparent power