Harmonic Measurement (Option) - YOKOGAWA WT1800 User Manual

6.6

Harmonic Measurement (Option)

Item
DUT
Method
Frequency range
PLL source
FFT data length
Window function
Anti-aliasing filter
Sample rates, window widths, and upper limits of harmonic analysis
6-12
Specifications
All installed elements
PLL synchronization method (no external sampling clock)
The range for the fundamental frequency of the PLL source is 0.5 Hz to 2.6 kHz.
• Select the voltage or current of each input element or an external clock.
• On models with the /G6 option, you can select two PLL sources and perform dual harmonic
measurement. On models with the /G5 option, you can select one PLL source.
• Input level
With voltage input, 15 V range or higher
With direct current input, 50 mA range or higher
With external current sensor input, 200 mV range or higher
50% or more of the rated measurement range when the crest factor is 3.
100% or more of the rated measurement range when the crest factor is 6.
20 Hz to 1 kHz for 1 A and 2 A ranges of 50 A elements.
• The conditions in which frequency filters are turned on are the same as those for frequency
measurements.
1024 when the data update rate is 50 ms, 100 ms, or 200 ms.
8192 when the data update rate is 500 ms, 1 s, 2 s, 5s, 10 s, or 20 s.
Rectangular
Set using the line filter
Number of FFT points: 1024 (when the data update rate is 50 ms, 100 ms, or 200 ms)
Fundamental
Frequency Sample Rate
15 Hz to 600 Hz f × 1024
600 Hz to 1200 Hz f × 512
1200 Hz to 2600 Hz f × 256
Number of FFT points: 8192 (when the data update rate is 500 ms, 1 s, 2 s, 5 s, 10 s, or 20 s)
Fundamental
Frequency Sample Rate
0.5 Hz to 1.5 Hz f × 8192
1.5 Hz to 5 Hz f × 4096
5 Hz to 10 Hz f × 2048
10 Hz to 600 Hz f × 1024
600 Hz to 1200 Hz f × 512
1200 Hz to 2600 Hz f × 256
However, when the data update rate is 50 ms, the maximum harmonic order that can be measured
is 100.
Upper Limit of Harmonic Analysis
Window
Width U, I, P, Φ, ΦU, ΦI
1 500
2 255
4 100
Upper Limit of Harmonic Analysis
Window
Width U, I, P, Φ, ΦU, ΦI
1 500
2 500
4 500
8 500
16 255
32 100
Other Measured
Values
100
100
100
Other Measured
Values
100
100
100
100
100
100
IM WT1801-03EN