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Flicker:
•
Pst:
The QNA-412 records the value of Flicker (Pst) obtained during the
recording period. The Plt value is calculated by the PC analysis software.
Harmonics:
Harmonic Distortion:
The QNA-412 will calculate and record the average
value of the harmonic distortion for voltage and current that has been
detected in the analysed system.
Harmonic Decomposition:
The QNA-412 will calculate and record the
average value of the rate of individual harmonic distortion for each of the
voltage and current harmonics in the analysed system (up to harmonic 40).
(Decomposition of each of the blocks of 10 cycles that have been
integrated within a recording period).
Wave Forms:
Voltage:
One cycle record of the voltage signal's wave form at the time of
ending the recording.
Current:
One cycle record of the current signal's wave form at the time of
ending the recording.
Unbalance:
Coefficient of asymmetry:
ratio between homopolar and direct voltage.
Coefficient of unbalance:
ratio between inverse and direct voltage.
8.2.2.-
EVENTS file (EVQ).
The different events detected in the analysed electrical system are stored in
this file. The following information is stored for each of the events:
Event Date:
This shows the time when the event occurred. This value is
obtained with an accuracy of one Cycle
Type of event:
This is stored if the detected event is an interruption, dip or
overvoltage. These events are defined according to the setting for the QNA-412. The
type of event also identifies the phase in which it occurred.
Duration of the Event:
How long the event lasted in milliseconds.
Maximum / minimum voltage of the Event:
In the event of an interruption or
dip the minimum voltage RMS½ value (*) obtained during the event will be stored. In
the event of overvoltage the maximum value will be stored.
Average voltage of the event:
Average voltage RMS½ value (*) obtained
during the recorded event.
Voltage prior to the event:
The voltage RMS½ value (*) prior to the event is
stored.
(*) value RMS½ cycle: effective value of one complete cycle, updated every half
cycle.
