PeakTech 4145 Bedienungsanleitung Seite 68

F1 Under 3-phase Y type wiring configuration, switch between voltage
readings of each phase (A/L1, B/L2, C/L3,N)or phase-phase (AB, BC,
CA).
F4 Access to the Trend screen.
F5 Switch between HOLD and RUN.
 Trend
All values in the Table screen are recorded, but the Trends from each row in the table
are displayed one at a time. Press function key F1 to switch between parameters.
The traces build up from the right side. Readings in the header correspond to the
most recent values plotted on the right.
Available function keys:
F1 Switch parameters that the current Trend screen displays, the header
shows content being displayed.
F4 Return to the Table screen.
F5 Switch between RUN and HOLD.
 Tips and Hints
Voltage and frequency should be close to the nominal values of for example 120V,
230V, 480V, 60Hz or 50Hz.
The voltages and currents in the table can be e.g. used to check if power applied to a
3-phase induction motor is in balance. Voltage unbalance causes high unbalanced
currents in stator windings resulting in overheating and reduced motor life. Each of
the phase voltages should not differ more than 1% from the average of the three.
Current unbalance should not exceed 10%. In case of too high unbalance, use other
measuring modes to further analyze the power system.
A Crest Factor close to 2.0 indicates high distortion. CF=2.0 can e.g. be found if you
measure the current drawn by rectifiers that only conduct at the sine wave top.
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