Hioki 3196 - Page 213

12.4 Formulae
207
Total harmonic voltage distortion factor THDUF (%)
Single-phase 2-wire
1P2W
Single-phase 3-wire
1P3W
Three-phase 3-wire
3P3W2M
Three-phase 3-wire
3P3W3M
Three-phase 4-wire
3P4W
THDUF1
THDUF4
THDUF1
THDUF2
THDUF4
THDUF12
THDUF32
THDUF4
THDUF12
THDUF23
THDUF31
THDUF4
THDUF1
THDUF2
THDUF3
THDUF4
• Calculate the Discrete Fourier Transform of harmonic RMS voltage at 2048 points (about once every 10
cycles at 50 Hz or every 12 cycles at 60 Hz).
• Three-phase 3-wire indicates the result of harmonic calculation with line-to-line voltage.
• In the equation above, K indicates the total of orders analyzed.
• Select THDUF or THDUR to calculate the total harmonic voltage distortion factor.
c: measured channel, k: order for analysis
THDUFc
U
ck()
2
k2=
K
∑
Uc1
-----------------------
100×=
Total harmonic current distortion factor THDIF (%)
Single-phase 2-wire
1P2W
Single-phase 3-wire
1P3W
Three-phase 3-wire
3P3W2M
Three-phase 3-wire
3P3W3M
Three-phase 4-wire
3P4W
THDIF1
THDIF4
THDIF1
THDIF2
THDIF4
THDIF1
THDIF2
THDIF4
THDIF1
THDIF2
THDIF3
THDIF4
THDIF1
THDIF2
THDIF3
THDIF4
• Calculate the Discrete Fourier Transform of harmonic RMS current at 2048 points (about once every 10
cycles at 50 Hz or every 12 cycles at 60 Hz).
• In the equation above, K indicates the total of orders analyzed.
• Select either THDIF or THDIR to calculate the total harmonic current distortion factor.
c: measured channel, k: order for analysis
THDIFc
I
ck()
2
k2=
K
∑
Ic1
---------------------
100×=
Total harmonic voltage distortion factor THDUR (%)
Single-phase 2-wire
1P2W
Single-phase 3-wire
1P3W
Three-phase 3-wire
3P3W2M
Three-phase 3-wire
3P3W3M
Three-phase 4-wire
3P4W
THDUR1
THDUR4
THDUR1
THDUR2
THDUR4
THDUR12
THDUR32
THDUR4
THDUR12
THDUR23
THDUR31
THDUR4
THDUR1
THDUR2
THDUR3
THDUR4
• Calculate the Discrete Fourier Transform of harmonic RMS voltage at 2048 points (about once every 10
cycles at 50 Hz or every 12 cycles at 60 Hz).
• Three-phase 3-wire indicates the result of harmonic calculation with line-to-line voltage.
• In the equation above, K indicates the total of orders analyzed.
• Select either THDUF or THDUR to calculate the total harmonic voltage distortion factor.
c: measured channel, k: order for analysis
THDURc
U
ck()
2
k2=
K
∑
Uck()
2
k1=
K
∑
-----------------------
100×=