Hioki 9605-01, Инструкция по эксплуатации, Страница: 13 / 100

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3.3 PLL Source Setting
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NOTE
3.3 PLL Source Setting
A PLL source is required for analysis, and may be provided in one of the
following three ways.
(1) Input voltage or current serves as the source:
Waveforms are sampled at a frequency synchronized with the measured
voltage or current waveform to facilitate correct measurement.
(2) Internal fixed clock [Clock] frequency serves as the source:
Use this options when the input signal is not suitable as a source of PLL
synchronization, and the fundamental frequency of the signal for analysis is
50 Hz. In this case, measurement accuracy cannot be assured at frequencies
other than integer multiples of 50 Hz.
(3) An external sync signal [Ext(CH6) or Ext(Con)] serves as the source:
PLL-synchronized measurements for harmonic analysis can be made using an
external signal other than the input voltage or current waveform. Refer to
Section 4.7, "Measurement using an External Sync Signal."
The PLL indicator at the upper right of the screen appears when the PLL is
unlocked, and is not visible when the PLL is locked. The source setting for
frequency measurement shares the same indicator.
1. Press the
STATUS
key, then use the
PAGE
keys
to move the cursor to "
HARM
," to display the
harmonic measurement setting screen.
2. Moving the cursor to "
PLL SOURCE
" with the
CURSOR
keys displays the settings available for
the PLL source in a window.
3. Use the
F1 "↓"
and
F2 "↑"
key to specify the
required item.
･
If the signal selected for the source setting is very distorted, if the level is
low for the range setting, or the signal frequency is not stable, the PLL
circuit may not function. In such cases accurate analysis is not possible.
･
If the three channels selected in Section 3.2 are separate systems with
different signal frequencies, the analysis results are only valid for the channel
for which the PLL source is set.