Hitachi HX-RIO3 Series User Manual page 22

22
HX-RIO3 Series
* Set Frequency to get the correct Power Factor & Energy.
*the reactive power measurement is negative when the load is capacitive, and when the load is inductive.
The sign of the reactive power can therefore be used to reflect the sign of the power factor.
Power Factor = (Sign Fundamental Reactive Power) * (abs(Active Power)/Apparent Power)