Fluke 345 Инструкция по эксплуатации онлайн [63/80] 4638

Fluke 345 Инструкция по эксплуатации онлайн [63/80] 4638
Power Quality Clamp Meter
Measurement Function Overview
49
The second screen shows the fundamental voltage ac (V ac [1]) and %THD as
shown in the following display.
eln33.bmp
As shown below in the A Harmonics screen, AUTO indicates the percentage is
automatically scaled to the max of H (2) and above. Pressing the H key for
3 seconds allows the scaling between values of 100 %, 40 %, 10 %, or 4 %,
and then back to AUTO. The automatic scaling feature is necessary, as
theoretically any harmonic beyond the fundamental can be as high as 600 %
with respect to the fundamental (H (1)), since the Clamp Meter supports THD
to 660 %. While 100 % can never be exceeded if %RMS is chosen from the
menu, the scale could go as high 700 % if harmonic type %H1 had been
selected. A scaling above 100 % is only available in the AUTO mode, where
the scaling could be 200, 300, 400, 500, 600, or 700 % full scale.

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