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Dears;
Refer to the Topic of Mr. Mill, I would like to mention the following points:
– The number of Harmonic is called “ Order ” ( Harmonic order 3 is the Third Harmonic “ 150 Hz ).
– The “ Soft Starter ” generates the Harmonics only in the starting & stopping steps, and as those steps are transient ( a few seconds ), so, in normal running no Harmonics are generated, and it’s considered that the “ Soft Starter ” are not Harmonics generator.
– The Elevator generates harmonics only if it’s controlled by VSD.
By the way, I want to mention that :
– “ IEC 61000-2-2 & 2-4 ” defined the maximum accepted level percentages of Voltage Harmonics in the LV Networks, either for Distribution Networks, or for privet networks connected to the utilities networks.
– “ IEC 61000-3-2 & 3-12 ” defined the maximum percentages of Current Harmonics that can be generated by electronic equipment, and even the maximum value of “ THD-I ”.