COMBI521
EN - 142
12.13. CALCULATION OF POWERS AND POWER FACTORS
The instrument measures the values of RMS Voltage and RMS Current and calculates the
average Power values for each period. The formulas for power calculation are:
N
i
i
i
i
v
N
P
1
1
N
i
i
N
i
i
i
N
v
N
S
1
2
1
2
1
1
2
2
P
S
Q
S
P
Pf
where:
N = number of samples in the period