Eaton Industrial Switchgear - xStart switching, protections and actuating motors

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2010 CA08103002Z-EN
10/16 Frequency inverters
Mains chokes, motor chokes
Mainschokes,motorchokes
Type overview
Application
Mains chokes (also called mains
chokes) are connected in series on the
mains side of electronic devices, such
as frequency inverters.
Features
The DEX-LN… line reactors are
vacuum-impregnated. Their air gaps
are therefore bridged with a low-
fatigue, metallically and magnetically
neutral connection, which reduces
noise emission.
Note: Because of the flux distribution
caused by their physical design, motor
chokes should be installed at a
distance of at least 50 mm from metal
parts and adjacent subassemblies.
Functions
Mains chokes attenuate any current
harmonics and peaks and limit the
starting current (internal DC link
capacitors). Through the reduction of
current harmonics, the r.m.s. value of
the absorbed current can be reduced
by up to 30 percent. In addition, mains
chokes permit a short-circuit voltage
to the mains (uk value) of about four
percent, which is often required.
Mains chokes also extend the lifespan
of components (rectifier diodes, DC
link capacitors) in devices with an
input-side internal DC link (frequency
inverters, USPs).
Documentation
Every line reactor is supplied with an
instructional leaflet (AWA 8240-1711).
The documentation is also available
for download from
DEX-LN1…
Mains chokes, single-phase
DEX-LN3…
Mains chokes, three-phase
Type overview
Application
Motor chokes are connected in series
to the output of frequency inverters.
Features
The DEX-LM3… motor chokes are
vacuum-impregnated. Their air gaps
are therefore bridged with a low-
fatigue, metallically and magnetically
neutral connection, which reduces
noise emission.
Motor chokes have larger dimensions
than comparable mains chokes with
the same rated operational current.
Note: Because of the flux distribution
caused by their physical design, motor
chokes should be installed at a
distance of at least 50 mm from metal
parts and adjacent subassemblies.
Functions
Motor chokes reduce the edge
gradient of the output voltage
(du/dt < 500 V/ms) of a frequency
inverter. They also reduce the motor’s
noise emission and heat generation.
Through the use of motor chokes the
permissible motor cable length can be
increased to up to 200 meters. When
operating several motors in parallel at
the output of a single frequency
inverter, the use of motor chokes is
recommended, as they attenuate the
high capacitive reactive currents.
Documentation
Every motor choke is supplied with an
instructional leaflet (AWA 8240-1711).
The documentation is also available
for download from
DEX-LM3…
Motor chokes, three-phase
DEX-LN…, DEX-LM3…