Satec Expertmeter EM720 Operation Manual page 210

Appendix E EN50160 Evaluation and Recording
Harmonic Voltage
Interharmonic Voltage
210
Method of Evaluation
The basic measurements are the individual harmonic
voltage distortion factors (HD) and the total harmonic
distortion factor (THD) over a period of 10 minutes under
normal operating conditions.
Harmonic voltages are evaluated by instrumentation
complying with IEC 61000-4-7. All calculations are made
relative to the nominal voltage.
The THD is evaluated including all harmonics up to the
order 40. Harmonic voltages are evaluated up the order
25 since the EN50160 provides target values for individual
harmonic voltages only for orders up to 25. The highest
harmonic order for evaluating individual harmonic voltages
and THD can be changed in the meter in the range of 25
to 50 via the EN50160 Advanced Setup.
Harmonic voltages are not evaluated if the supply voltage
crosses a voltage tolerance limit (±15% Un).
Target Values
The ranges of harmonic voltages given in the EN50160
are:
• THD % for 95% of a week
≤ 8
• Individual harmonic voltages shall be less than or
equal to the values given in Table 1 Clause 2.11 of
the EN50160 for 95% of a week.
The THD compliance limit can be changed in the meter via
the EN50160 PQ Recorder setup. The individual harmonic
voltage limits can be adjusted via the EN50160 Harmonics
setup.
Method of Evaluation
Since the EN50160 does not specify target limits for
interharmonic voltages, this feature is normally disabled in
your meter. You can enable evaluation of interharmonic
voltages via the EN50160 Advanced Setup.
The basic measurements are the individual interharmonic
voltage distortion factors (HD) and the total interharmonic
distortion factor (THD) over a period of 10 minutes under
normal operating conditions.
Interharmonic voltages are evaluated by instrumentation
complying with IEC 61000-4-7. All calculations are made
relative to the nominal voltage.
The highest harmonic order for evaluating individual
interharmonic voltages and interharmonic THD can be
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