Line Filters - Siemens SINAMICS G130 Engineering Manual

A line reactor can only be dispensed with when the RSC value for relative short-circuit power is less than stated in
the above table. This applies, for example, if the converter is connected to the supply via a transformer with specially
adapted rating and none of the other reasons stated above for using a line reactor is valid.
Transformer connection
S
k2 Line
Supply
Supply cable
inductance
In this case, the short-circuit power S
S
=
Transf
S
k 1
S
+
Transf
u
k Transf
S
k 2 Line
Abbreviation Meaning
S Rated power of the transformer
Transf
u Relative short-circuit power of the transformer
k Transf
S Short-circuit power of the higher-level voltage
k2 Line
Line reactors must always be provided if more than one converter is connected to the same point of common
coupling. In this case, the reactors perform two functions, i.e. they smooth the line current and decouple the rectifiers
at the line side. This decoupling is essential in ensuring fault-free operation of the rectifier circuit. For this reason,
each converter must be provided with its own line reactor, i.e. it is not permissible for more than one converter to be
connected to the same line reactor.
A line reactor must also be installed for any converter that is to be equipped with a line filter for RFI suppression or
with a Line Harmonics Filter (LHF) for reducing harmonic effects on the supply. This is because filters of this type
cannot be 100% effective without a line reactor.

Line filters

SINAMICS G130 Chassis are equipped as standard with an integrated line filter for limiting radio frequency
interference emissions in accordance with EMC product standard EN 61800-3, category C3 (applications in industrial
areas or in the "second" environment).
An optional line filter is also available which renders the units suitable for category C2 applications in accordance with
product standard EN 61800-3 (installation in residential areas or in the "first" environment).
To ensure that the converters comply with the tolerance limits defined for the above categories, it is absolutely
essential that the relevant installation guidelines are followed. The efficiency of the filters as regards grounding and
shielding can be guaranteed only if the drive is properly installed.
Line filters can be used only on converters that are connected to grounded supply systems (TN or TT). On converters
connected to non-grounded systems (IT supply systems), the standard integrated line filter must be isolated from PE
potential. This can be done simply by removing a metal clip on the filter when the drive is commissioned (see
operating instructions). It is not permissible to use the optional line filter in non-grounded systems to achieve
compliance with the tolerance limits defined for category C2 by EMC product standard EN 61800-3.
For further details about line filters, please refer to the section "Line filters" of the chapter "Fundamental Principles
and System Description".
Converter connection
point point PCC
S S
Transf k1
u
k Transf
at the PCC of the converter is approximately
k1
Engineering Information
Converter
SINAMICS Engineering Manual - May 2008
SINAMICS G130
181/396
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