Harmonics - PeakTech 4145 Bedienungsanleitung

By monitoring the voltage and current trend at the power service entrance, you can
find out of the cause of the voltage dip is inside or outside the building. The cause is
inside the building (downstream) when voltage drops while current rises; it is outside
(upstream) when both voltage and current drop.

7.4 Harmonics

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Harmonics measure and record harmonics and interharmonics up to the 50 . Related
data such as DC components, (THD) Total Harmonic Distortion, and K-factor are
measured. Harmonics are periodic distortions of voltage, current or power sinewave.
A voltage or waveform can be considered as a combination of various sinewaves
with different frequencies and magnitudes. The contribution of each of these
components to the fundamental signal is measured. Readings can be given as a
percentage of the fundamental (%f), or as a percentage of full signal RMS
(%r).Results may be viewed in a Bar Graph display. Harmonics are often caused by
non-linear loads such as DC power supplies in computers, TV's and adjustable
speed motor drives. Harmonics can cause transformers, conductors, and motors to
overheat.
 Bar Graph Screen
The Bar Graph display shows the percentage contribution of each of the components
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related to the fundamental or full signal. A signal without distortion should show a 1
harmonic at 100% while the others are at 0: in practice this will not occur because
there always is a certain amount of harmonics resulting in distortion.
A sinewave becomes distorted when harmonics components are added to it.
Distortion is represented by the Total Harmonic Distortion (THD) percentage. The
display can also show the percentage of the DC component and each harmonic ratio.
The left/right arrow keys are used to position the Cursor on particular bar. The screen
header will show for that bar phase identifier, harmonic component ratio, frequency
and phase angle. If not all bars are shown on the screen, you can bring the next set
within the viewing area by moving the Cursor off the left or right end of the screen.
Available function keys:
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