Hioki 8847 - 13.7 Printing Analysis Results

13.3 Setting FFT Analysis Conditions
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13
Chapter 13 FFT Function
 Total harmonic distortion (THD)
When the analysis mode is one of the following, the cursor appears and the distortion rate is calculated.
(Linear spectrum, RMS spectrum, power spectrum)
The distortion rate calculates the cursor position as the fundamental wave. When 2 cursors appear, the A
cursor becomes the fundamental wave.
When calculation results cannot be obtained, [---%] is displayed.
Note that distortion rate values may become higher depending on the window function settings.
THD
Σ f
n
()
2
f
0
()
2
---------------
100×=
f
0
=fundamental wave
f
n
= n next higher harmonic
[%]