PeakTech 4145 Bedienungsanleitung Seite 73

F1 Selection of harmonics type: voltage, current.
F2 Selection of bar set to be displayed: L1, L2, L3, N or all
F3 Interharmonics display on/off
F4 Open the table screen
F5 Switch between RUN and HOLD.
 Table Screen
The table screen lists all the harmonic parameters, including Harmonic Voltage,
Harmonic Current, Interharmonic Voltage and Simple Harmonic Current. Select next
page with up/down keys.
Available function keys:
F3 Take fundamental voltage as percentage reference (%f) or total harmonic
voltage as percentage reference (%r)
F4 Open the bar graph screen of harmonic
F5 Switch between RUN and HOLD.
 Tips and Hints
The harmonic number indicates the harmonic frequency: the first harmonic is the
fundamental frequency (60 or 50Hz); the second harmonic is the component with
two times the fundamental frequency (120 or 100Hz), and so on. The harmonics
sequence can be positive (1, 4, 7...), zero (3, 6, 9...) or negative (2, 5, 8...). Positive
sequence harmonics try to make a motor run faster than the fundamental, negative
sequence harmonics try to make a motor run slower than the fundamental. In both
cases the motor looses torque and heats up. Harmonics can also cause transformers
to overheat. Even harmonics disappear if waveforms are symmetrical, i.e. as equally
positive and negative.
Zero sequence current harmonics add in Neutral conductors. This can cause
overheating of these conductors, and make ground potential rising..
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