Iskra MC330 - Thd

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APPENDIXE:CALCULATIONS&EQUATIONS
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74 Measuringcentres
–
MC320,MC330,MC350&MC350H‐User’sManua
l
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THD


100%
1
63
2
2



I
I
THDI
n
n
f
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CurrentTHD
I
1
‐valueoffirstharmonic
n‐numberofharmonic

100%
1
63
2
2



f
n
fn
f
U
U
THDU
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PhasevoltageTHD
U
1
‐valueoffirstharmonic
n‐numberofharmonic

100%
1
63
2
2



ff
n
ffn
ff
U
U
THDU
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Phase‐to‐phasevoltageTHD
U
1
‐valueoffirstharmonic
n‐numberofharmonic
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