Hioki PQ3198, Инструкция по эксплуатации

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Voltage swell
(SURGE)
Swells occur when the
voltage rises momen-
tarily, for example when
a power line turns on or
off due to lightning or a
heavy load, when a
high-capacity capacitor
bank is switched, when
a one-line ground
occurs, or when a high-
capacity load is cut off.
This phenomenon also
includes voltage surges
due to grid-tied dis-
persed power supplies
(solar power, etc.).
A surge in voltage may
cause the device's
power to be damaged
or the device to reset.
Events are detected
using swells.
Flicker
Flicker consists of volt-
age fluctuations result-
ing from causes such
as blast furnace, arc
welding, and thyristor
control loads. Manifes-
tations include light
bulb flicker.
Because this phenom-
enon reoccurs regu-
larly, it may cause the
light to flicker or the
device to malfunction.
Large flicker values
indicate that most peo-
ple would find the flick-
ering of lighting
unpleasant.
Events are measured
using Δ V10 flicker and
IEC flicker Pst and Plt.
Interruption
(momentary
power outage)
Interruptions consist of
momentary, short-
term, or extended
power supply outages
as a result of factors
such as circuit break-
ers being tripped due
primarily to power
company issues (inter-
ruption of power due
to lightning strikes,
etc.) or power supply
short-circuits.
Recently, due to the
spread of UPS (unin-
terruptible power
sources), most of
these problems can be
fixed using a com-
puter, but this may
cause the device to
stop operating due to
an interruption or to
reset.
Events are detected
using interruptions.
Harmonic
Harmonics are caused
by distortions of the
voltage and current
waveforms when a
device’s power supply
uses semiconductor
control devices.
Large harmonic com-
ponents can lead to
major malfunctions,
including overheating
of motors and trans-
formers and burnout of
reactors connected to
phase advance capac-
itors.
Events are detected
using harmonic volt-
age, harmonic cur-
rent, and harmonic
power. They can also
be detected as voltage
waveform distortions
using voltage wave-
form comparison func-
tionality.
Inter-harmonics
Inter-harmonics are
caused when the volt-
age or current wave-
form is distorted due to
static frequency con-
version equipment,
cycloconverters,
Scherbius machines,
induction motors,
welders, or arc fur-
naces. The term refers
to frequency compo-
nents that are not a
whole multiple of the
fundamental wave.
Displacement of the
voltage waveform
zero-cross may dam-
age equipment, cause
it to malfunction, or
degrade its perfor-
mance.
Inter-harmonics are
measured using inter-
harmonic voltage and
inter-harmonic cur-
rent. Events are not
supported, but it may
be possible to detect
events as voltage
waveform distortions
using voltage wave-
form comparison func-
tionality.
Principal
parameters
indicating
power quality
Waveform Phenomenon Primary issues
PQ3198 events and
measurements
HIOKI PQ3198A961-03