Insulated Bearings For Converter Operation - Siemens SIMOTICS M-1PH8 Operating Instructions & Installation Instructions

Preparations for use
4.12 Converter operation
Measures to 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 prevent bearing currents:
● Setting up a properly meshed grounding system in the system as a whole, with low
● No potential difference between the motor, converter, and working machine.
● Use iron cores mounted above the motor connecting cable at the converter output. These
● Limit the voltage rate of rise by using an output filter to dampen harmonic components in
4.12.2

Insulated bearings for converter operation

If the machine is operated at a low-voltage converter such as SINAMICS G150 / S150 / S120,
then an insulated bearing and a speed encoder with insulated storage (option) is mounted on
the non-drive end.
For 1PH818, the insulated bearings are optional; for 1PH822 and 1PH828, insulated bearings
are standard.
Comply with the plates on the machine relating to bearing insulation and possible bridges.
①
②
③
Figure 4-4
42
impedance for high-frequency currents
– Use symmetrical, shielded connecting cables.
– Connect the cable shield at both ends over the greatest possible surface area (360°
contact).
– Use equipotential bonding conductors between the motor and the driven machine as
well as between the motor and the converter
help to reduce common-mode components. The Siemens sales representative is
responsible for selection and dimensioning.
the output voltage
Driving machine
Motor
Coupling
Schematic representation of a single drive
④
Insulated bearings
⑤
Insulated tachometer fitting
Operating Instructions 05/2012 A5E03986435A AA
SIMOTICS M-1PH8