TM
3-9) Harmonics Index (HIX)
4) Neutrals to overheat due to triplen harmonics
present on the neutral (150Hz or 180Hz)
5) Bus bars and electrical panels to vibrate
Harmonics are unwanted AC voltages or currents with
frequencies that are multiples of the fundamental
frequency, which produce non-sinusoidal waveforms.
Harmonic currents are typically caused by solid state
lighting ballasts, solenoids, motor controllers, switching
power supplies or any other nonlinear load. Harmonics
normally appear in the Current waveforms, however, the
current harmonics will distort the system voltage
waveform and cause voltage harmonics when the
system impedance is relatively high. These voltage
harmonics will then affect other devices within the same
system.
In the past, to identify the presence of harmonics which
cause problems to your system, you may need an
expensive instrument to see the complete harmonic
spectrum with respect to fundamental frequency. Now,
TM
harmonics index (HIX) function offers an alternative to
indicate the presence of harmonics by a hand held
digital multimeter in a cost effective way.
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TM
Harmonics Index (HIX) function generates a comparative
percentage index between 0% to 100% to indicate the
deviation of non-sinusoidal to sinusoidal waveform, which is
a good indication of the presence of harmonics. Pure
sinusoidal waveform without harmonics has a harmonics
TM
TM
index value of 0%. The higher the harmonics index
value, the more the harmonics are present. Harmonics
TM
index value examples are given in table 2 for your
reference. Please note that in cases where the harmonics
are mostly 3rd (triplen), the neutral current can be a nearly
pure sine wave at the harmonic frequency of 150Hz or
180Hz tripien) Which can often be detected by measuring
the frequency of the netural current.
INPUT
WAVEFORM
DESCRIPTION
HIX VALUE
a) No distortion,
pure Sinusoidal,
y=100sin(
w
t)
0%
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