Total Harmonic Distortion (Thd); Reactive Power Compensation Devices; Cable Cross-Sections - Eaton PowerXL DC1 20 Series Installation Manual

2.2.4 Total Harmonic Distortion (THD)

2.2.5 Reactive power compensation devices

2.3 Cable cross-sections

The THD value (THD = Total Harmonic Distortion) is defined in standard
IEC/EN 61800-3 as the ratio of the rms value of all harmonic components to
the rms value of the fundamental frequency.
￫
In order to reduce the THD value (up to 30%), it is
recommended to use a DX-LN... mains choke
(￫ Section 2.5, "Mains chokes", page 43).
Compensation on the power supply side is not required for the variable
frequency drives of the DC1 series. From the AC power supply network they
only take on very little reactive power of the fundamental harmonics
(cos ϕ ~ 0.98).
￫
In the AC supply systems with non-choked reactive current
compensation devices, current deviations can enable parallel
resonance and undefinable circumstances.
In the project planning for the connection of variable frequency
drives to AC supply systems with undefined circumstances,
consider using mains chokes.
The mains cables and motor cables must be sized as required by local
standards and by the load currents that will be involved.
The PE conductor's cross-sectional area must be the same as the phase
conductors' cross-sectional area. The connection terminals marked with 
must be connected to the earth-current circuit.
NOTICE
The specified minimum PE conductor cross-sections
(EN 61800-5-1) must be maintained.
If there are leakage currents greater than 3.5 mA, a reinforced earthing (PE)
must be connected, as required by standard EN 61800-5-1. The cable cross-
section must be at least 10 mm
separately connected earthing cables.
￫
￫ Section 6.2, "Specific rated operational data", page 149
provides the leakage currents for the individual models.
￫
￫ Section 3.5, "EMC installation", page 70 goes over the EMC
requirements for the motor cables.
DC1...20... and DC1...OE1 Variable Frequency Drives 02/20 MN040059EN www.eaton.com
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, or the earthing system must consist of two
2 Engineering
2.3 Cable cross-sections
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