User manual

PQM-702, PQM-703 Operating Manual
52
 for events related to DC voltage and U
N-PE
voltage, the hysteresis is calculated as a percentage
of the threshold value, but not less than 50 mV (referred to input).
 for remaining parameters, the hysteresis is specified as a percent of maximum threshold (e.g.
when maximum threshold for current crest factor has been set to 4.0 the hysteresis is 0.02×4.0
= 0.08.)
3.13 Methods of parameter‘s averaging
Method of parameter averaging
Parameter
Averaging method
RMS voltage, RMS current
RMS
DC voltage, DC current
arithmetic average
Frequency
arithmetic average
Crest factor U, I
arithmetic average
Symmetrical components U, I
RMS
Unbalance factor U, I
calculated from average values of symmetrical components
Active, Reactive, Apparent and
Distortion Power
arithmetic average
Power Factor PF
calculated from the averaged power values
cos
arithmetic average
tan
calculated from the averaged power values
THD U, I
calculated as the ratio of the RMS value of the higher order harmonics to
the RMS value of the fundamental component (for THD-F), or the ratio of
the RMS value of higher oreder harmonics to the total RMS voltage (for
THD-R)
TID U, I
calculated as the ratio of the RMS value of interharmonics to the RMS
value of the fundamental component (for TID-F), or the ratio of the RMS
value of interharmonics to the total RMS voltage (for TID-R)
Harmonic amplitudes U, I
RMS
Interharmonic amplitudes U, I
RMS
K-factor
RMS
The angles between voltage
and current harmonics
arithmetic average
Active and reactive power of
harmonics
arithmetic average
Note:
RMS average value is calculated according to the formula:




 




The arithmetic average (AVG) is calculated according to the formula:







where:
 X
i
is subsequent parameter value to be averaged,
 N is the number of values to be averaged.