Hioki 3196 - Page 28

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<Reference> Harmonic Inflow/Outflow judgment on a measurement instrument
-1.
Judge the inflow/outflow by the polarity of the harmonic (effective) power. (Judge each
phase and each order independently.)
Judgment by harmonic power
-2.
Judge the inflow or outflow by the harmonic voltage-current phase difference (difference
between harmonic voltage phase angle and harmonic current phase angle).
For 3-phase 3-wire (3P3W2M or 3P3W3M) installations, we recommend using the harmonic
voltage-current phase difference of "sum" value.
Judgment by the harmonic voltage-current phase difference
Inflow
Outflow
Harmonic power is + (positive).
Harmonic power is - (negative).
Problem
The higher the order, the smaller the harmonics power level.
The smaller level makes it difficult to judge the polarity accurately, thus
making it difficult to judge inflow and outflow.
Inflow
Outflow
-90 to 0 to +90 degrees
-180 to -90 degrees, +90 to +180 degrees
Harmonic voltage-current phase angle
Problem
Judge to see if the high harmonic current level exceeds the limit. Do
not watch the harmonic current amplitude level.
Then, judge the inflow or outflow by watching the harmonic voltage-
current phase difference.
LEAD
LAG
InflowOutflow
Voltage-Current
Phase Difference
+90deg.
-90deg.
0deg.+/-180deg.