Siemens 1LA8, Руководство по эксплуатации

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Measures to further reduce bearing currents
To specifically reduce and prevent damage caused by bearing currents, you must consider
the system as a whole, which comprises the motor, converter, and driven machine. The
following precautions help to reduce bearing currents:
● In the overall system, set up a properly meshed grounding system with low impedance for
high-frequency currents.
● Use the common-mode filter (damping cores) at the converter output. The Siemens sales
representative is responsible for selection and dimensioning.
● Limit the rise in voltage by using output filters. This dampens the harmonic content in the
output voltage.
Note
Converter documentation
The operating instructions for the converter are not part of this documentation. Refer also
to the configuration information for the converter.
6.5.6.4 Converter operation on a grounded network
NOTICE
Damage resulting from protective conductor currents
When the machine is operated on a converter with current limiter, but without ground-fault
monitoring, protective conductor currents of up to 1.7 times the external conductor current
can arise if there is a ground fault on the output side. Neither the PE conductors of normally
rated multi-core connecting cables nor the PE connecting points of normal terminal boxes
are suitable for this purpose. Material damage can result.
● Use an appropriately sized PE conductor.
● Connect the PE conductor to the grounding terminal on the motor enclosure.
Electrical connection
6.5 Connecting the auxiliary circuits
SIMOTICS TN Series N-compact 1LA8
82
Operating Instructions 05/2014