Ceyear 4051 Series, User Manual

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4. Operating Instruction
4.2 Advanced operation guide
106
Fig. 4.22 Display interface of second harmonic amplitude
Step 10. calculate harmonic distortion:
 Use the relation shown in Fig. 4.20 to convert distortion percentage between the second harmonic and the
fundamental wave. The unit can be changed again to volt in order to read the voltage ratio of two signals.
Repeat step 9 - 10 for other harmonics to be measured to get their distortion percentage. Total signal harmonic
distortion percentage is also subject to frequent test. In order to test such parameter, amplitude of each
harmonic should be tested with linear unit (such as volt) rather than relative unit dBc.
Step 11. measure total harmonic:
 Press
【
Amplitude/Y Axis
】
, [More 1/2>>], [Y Axis Unit
▶
] and [V] and set amplitude unit as volt.
Measured signal amplitude may be used in the following equation to calculate total harmonic distortion:
Total harmonic distortion
Where:
A
1
refers to fundamental wave amplitude (V)
A
2
refers to second harmonic amplitude (V)
A
3
refers to fundamental wave amplitude (V)
A
n
refers to nth harmonic amplitude (V)
If the signal amplitude is measured carefully as indicated above, measured harmonic distortion percentage will
be very accurate.