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IM WT3001E-51EN
7.11 Harmonic Measurement Specifications
Item
Specifications
Measured source
All installed elements
Format
PLL synchronization method
Frequency range
Fundamental frequency of the PLL source is in the range of 10 Hz to 2600 Hz.
PLL source
• Select the voltage or current of each input element (external current sensor range is greater
than or equal to 500 mV) or the external clock (Ext Clk).
• Input level
Greater than or equal to 50% of the measurement range rating when the crest factor is 3
Greater than or equal to 100% of the measurement range rating when the crest factor is 6
• Turn the frequency filter ON when the fundamental frequency is less than or equal to 440 Hz.
Measurement function
See the next section.
FFT data length
9000
FFT processing word length 32 bits
Window function
Rectangular
Anti-aliasing filter
Set using a line filter (5.5 kHz or 50 kHz).
Sample rate (sampling frequency), window width, and upper limit of measured order during PLL synchronization
Fundamental
Frequency of
the PLL Source
(Hz)
Sample Rate
(S/s)
Window Width against
the FFT Data Length
(Frequency of the
Fundamental Wave)
Upper Limit of
the Measured Order
10 to 20
f × 3000
3
100
20 to 40
f × 1500
6
100
40 to 55
f × 900
10
100
55 to 75
f × 750
12
100
75 to 150
f × 450
20
50
150 to 440
f × 360
25
15
440 to 1100
f × 150
60
7
1100 to 2600
f × 60
150
3
For the specifications of the wide bandwidth harmonic measurement and IEC harmonic
measurement, see chapters 8 and 9.
