Siemens 1PH728, Operating Instructions Manual

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Maintenance
7.1 Maintenance
A5E00177602A AD
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Siemens AG Operating Instructions 2.02 1PH728
WARNING
Impeller can crack
Due to deposits and the resulting imbalance there is a hazard of fatigue fracture of the
impeller. The impeller can crack in operation. Death, serious injury, or material damage
can result.
Regularly clean and inspect the fan.
● Refer to the maintenance and service information provided by the manufacturer of the
external fan.
7.1.4 Bearings
Description
The three-phase motors have grease-lubricated, rolling-contact bearings. A regreasing
device is available.
A deep-groove ball bearing is installed at the NDE as a locating bearing. Depending on the
type of load, a deep-groove ball bearing or cylindrical-roller bearing is installed at the DE as
a floating bearing.
For the bearing assignments as well as the associated permissible lateral forces and
minimum loads when cylindrical-roller bearings are installed at the DE, refer to the catalog or
contact us.
Preloading springs, thrust collars, and/or equalizing rings are installed in the active part of
the bearing at the DE to provide backlash compensation for the outer races. Due to the
operation at the frequency converter, the bearing at the NDE is electrically insulated.
[ID: 358.01]
7.1.5 Lubrication
Relubrication intervals
The relubrication intervals are stated on the lubrication instruction plate of the three-phase
motor.
NOTICE
Observe the basic lubrication interval (see section entitled "Measures, intervals").
NOTICE
If there is a long interval between delivery and commissioning of the motor, the bearings
must be relubricated.