1-10
IM WT310E-01EN
Measurement Period (For procedures, see section 2.8)
Measurement Period for Measurement Functions Used in Normal
Measurement
The measurement period is determined by the input signal that is used as the reference (synchronization
source). The measurement period is set within the data update interval between the first point where the
sync source crosses the level-zero point (center of the amplitude) on a rising slope (or falling slope) and
the last point where the sync source crosses the level-zero point on a rising slope (or falling slope).
Data update interval:
Measurement period
Synchronization
source
Rising zero crossing
Falling zero crossing
If there is not more than one rising or falling slope within the data update interval, the entire data
update interval is set as the measurement period.
Data update interval:
Measurement period
Synchronization
source
The measurement period for determining the numeric data of the peak voltage or peak current is
always the entire span of the data update interval. Therefore, the measurement period for the following
measurement functions, which are determined on the basis of the maximum voltage or current, is also
the entire span of the data update interval.
Peak voltage (U+pk/U-pk), peak current (I+pk/I-pk), and peak power (P+pk/P-pk)
For details, see appendix 5.
Measurement Period for Measurement Functions Used in
Harmonic Measurement (Option)
The measurement period extends from the first sample in the data update interval for 1024 points,
counted at the harmonic sampling frequency.
This instrument determines the harmonic sampling frequency automatically based on the period of
the signal that is set as the PLL source. The sampling data and measurement period that are used
to determine the values of harmonic measurement functions may be different from those used to
determine the values of normal measurement functions.
Data Update Interval (For procedures, see section 2.10)
The data update interval is the interval at which sampled data is acquired and measurement functions
are computed, displayed, transmitted, and output through D/A conversion.
You can select the data update interval from the options below.
0.1 s, 0.25 s, 0.5 s, 1 s, 2 s, 5 s, 10 s, 20 s or Auto
At each data update interval, the numeric data is updated, stored, converted and output as analog
signals, and transmitted through the communication interface.
When set to Auto, every time a period of the input waveform specified as the synchronization source
is detected, measured data is updated, output as analog signals, and transmitted through the
communication interface.
To capture relatively fast load fluctuations in the power system, select a fast data update interval. To
capture low frequency signals, select a slow data update interval.
If the fluctuation in the input signal period is large, select Auto.
1.2 Measurement Conditions
