Siemens LOHER CHEMSTAR 1PS2, Operating Instructions And Installation

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inspected for mechanical damage which could constitute a risk of ignition in accordance with
IEC / EN 60079‑17 .
● Comply with the following intervals:
– Bearing replacement intervals
– Relubrication intervals
– Grease replacement intervals
– Oil change intervals
● Roller bearing service life
– Replace the roller bearings once the nominal service life is reached. Alternatively, you
can verify they are free of mechanical damage as part of an inspection.
– In the case of roller bearings without a regreasing system, it is ensured that the nominal
service life will only be achieved clearly after achievement of the service life of the grease
in the bearings.
– The roller bearing service life under full specified load is at least 20 000 hours for
machines subject to radial or axial forces.
– The nominal roller bearing service life of machines which are not subject to any forces
is at least 40 000 hours.
● For roller bearings with external oil supply, monitor that lubrication is maintained.
9.1.7 Maintenance
9.1.7.1 Insulation resistance and polarization index
Measuring the insulation resistance and polarization index (PI) provides information on the
condition of the machine. It is therefore important to check the insulation resistance and the
polarization index at the following times:
● Before starting up a machine for the first time
● After an extended period in storage or downtime
● Within the scope of maintenance work
The following information is provided regarding the state of the winding insulation:
● Is the winding head insulation conductively contaminated?
● Has the winding insulation absorbed moisture?
As such, you can determine whether the machine needs commissioning or any necessary
measures such as cleaning and/or drying the winding:
● Can the machine be put into operation?
● Must the windings be cleaned or dried?
Detailed information on testing and the limit values can be found here:
"Testing the insulation resistance and polarization index"
Maintenance
9.1 Inspection and maintenance
LOHER CHEMSTAR 1PS2
Operating Instructions 08/2016
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