Standards And Permissible Harmonics - Siemens SINAMICS G130 Engineering Manual

Standards and permissible harmonics

A number of key standards which define the permissible limit values for harmonics are listed below.
EN 61000-2-2
Compatibility Levels for Low-Frequency Conducted Disturbances and Signaling in Public Low-Voltage Power
Supply Systems
This European standard deals with conducted disturbance variables in the frequency range from 0 Hz to 9 kHz. It
specifies the compatibility levels for low-voltage AC supply systems with a rated voltage of up to 420 V 1-phase, or
690 V 3-phase and a rated frequency of 50 Hz or 60 Hz.
The compatibility levels specified in this standard are valid for the PCC (Point of Common Coupling) with the public
supply system.
Limits for harmonic currents are not defined. Limits are specified only for harmonic voltages and the total harmonic
distortion of the voltage THD(V).
The limits for the PCC with the public supply system are identical to the limits of Class 2 according to EN 61000-2-4
(see below).
The corresponding compatibility level for the total harmonic distortion THD(V) is 8 %.
EN 61000-2-4
Compatibility Levels for Low-Frequency Conducted Disturbances in Industrial Plants
This European standard deals with conducted disturbance variables in the frequency range from 0 Hz to 9 kHz. It
specifies compatibility levels in numbers for industrial and private supply systems with rated voltages up to 35 kV and
a rated frequency of 50 Hz or 60 Hz.
Supply systems on ships, aircraft, offshore platforms and railways are not in the field of application of this standard.
EN 61000-2-4 defines three electromagnetic environmental classes:
Class 1 This class applies to protected supplies and has compatibility levels that are lower than the level of the
public supply system. It refers to equipment that is very sensitive to disturbance variables in the power
supply, e.g. electrical equipment of technical laboratories, certain automation and protection equipment,
certain data processing equipment etc.
Class 2 This class generally applies to PCCs (Points of Common Coupling) with the public supply system and to
IPCs (Internal Points of Coupling) with industrial or other private supply systems. The compatibility
levels for this class are generally identical to those for public supply systems. Therefore components
that have been developed for operation on public supply systems can be used in this industrial
environment class.
Class 3 This class applies only to IPCs (Internal Points of Coupling) in industrial environments. It has higher
compatibility levels for some disturbance variables than Class 2. For example, this class should be
considered when one of the following conditions applies:
•
The main part of the load is supplied via converters;
•
Welding machines are used;
•
Large motors are started frequently;
•
Loads vary quickly.
The class that is to be used for new plants or expansions to existing plants cannot be defined in advance, but
depends on the intended type of installation (of equipment, device) and the process.
Fundamental Principles and System Description
Engineering Information
SINAMICS Engineering Manual - May 2008
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