Preparing for use
4.13 Converter operation
Standard motors SH 63 ... 355
42
Operating Instructions, 12/2018, A5E38483075A
●
If the cable shield is not connected due to special secondary conditions, or not
adequately connected, then the specified equipotential bonding is not provided. In this
particular case, use a separate RF equipotential bonding conductor:
–
Between the motor enclosure and protective ground rail of the converter.
–
Between motor enclosure and driven machine
–
Use braided flat copper straps or high-frequency cables with finely-stranded
conductors for the separate RF equipotential bonding cable.
–
Ensure that the contacts are made over a large area.
Measures to reduce bearing currents
To specifically reduce bearing currents, you must consider the system as a whole, which
comprises the motor, converter, and driven machine. The following measures support you
when reducing bearing currents and help to avoid damage:
●
In the overall system, set up a properly meshed grounding system with low impedance.
●
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. Output filters dampen the harmonic content
in the output voltage.
●
The operating instructions for the converter are not part of this documentation. Refer to
the configuration information for the converter.
4.13.4
Insulated bearings when operated with a converter
If the machine is operated from a low-voltage converter, insulated bearings are fitted at the
NDE and an insulated encoder with insulated bearings (option).
Comply with the plates on the machine relating to bearing insulation and possible bridges.
①
Driving machine
④
Insulated bearings
②
Motor
⑤
Insulated tachometer fitting
③
Coupling
Figure 4-2
Schematic representation of a single drive
