Hioki 8847, Instruction Manual

Page: 228 / 372

13.3 Setting FFT Analysis Conditions
218

Trigger Modes and Averaging
If the trigger mode is [Single] or the calculation setting is [Once]
Measurements continue until the specified number of averaging points is acquired.
If the trigger mode is [Continue] or the calculation setting is [Repeat]
Measurement continues after the specified averaging count has been acquired.
When the specified averaging count is exceeded, averaging is repeated and measurement continues until the
STOP
key is pressed.
When the trigger mode is [Auto]
•For time-domain waveforms:
Data is acquired when the START key is pressed, even if trigger criteria are not met after a certain
interval. So if averaging is applied to an asynchronous signal, the resulting data is meaningless.
•For spectrum values:
When the START key is pressed, measurement starts. Even if the trigger criteria are not met, the spec-
ified amount of data is acquired, and after FFT analysis, the results are averaged.
When the specified averaging count is exceeded, averaging is repeated and measurement continues
until the
STOP key is pressed.
When the acquired count < the specified count *
1
When the acquired
count = the speci-
fied count
Start Measurement
START key
End *
2
Trigger
criteria met
Input
Signal
Awaiting
Trigger
Waveform acquisi-
tion (specified no.
of points)
Averaging
Display*
3
FFT
analysis
(Spectrum averaging) (Waveform averaging)
*1. Awaiting trigger continues until the specified count is reached.
*2. Measurement stops automatically when the specified count is
reached. If measurement was interrupted by the STOP key, the
averaging result up to that point is displayed.
*3 If [Reference] is [New Data] and the automatic saving or auto-
matic print setting is ON, data is saved or printed when the spec-
ified number of times is reached.
FFT
analysis
Repeats until the STOP key is pressed
Start Measurement
START key
End*
1
Trigger
criteria met
Input
Signal
Awaiting
Trigger
Waveform acquisi-
tion (specified no.
of points)
Averaging
Display*
2
FFT
analysis
(Spectrum averaging) (Waveform averaging)
*1 When stopped before the specified count, the average up to that point is displayed.
*2 If
[Reference] is
[New Data]
and the automatic saving or automatic print setting is On,
data is saved or printed when the specified number of times is reached.
FFT
analysis
STOP key
Repeats until the STOP key is pressed
Start Measurement
START key
End*
After a certain interval,
acquisition starts even if
trigger criteria are not met
Input
Signal
Awaiting
Trigger
Waveform acquisi-
tion (specified no.
of points)
Averaging
Display
FFT
analysis
(Spectrum averaging) (Waveform averaging)
* When stopped before the specified count, the average up to that point is displayed.
FFT
analysis