Siemens SIMOTICS DP, Operating Instructions Manual

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9.2.11 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"
9.2.12 Servicing the separately driven fan
WARNING
Injury caused by rotating parts or live (under voltage) parts
Live electrical parts are dangerous. Contact with them can cause death, serious injury or
material damage.
• Before carrying out any maintenance work on the separately driven fan, disconnect it from
the mains, particularly before opening the terminal box.
• Make sure that the device cannot be switched back on.
Servicing the separately driven fan
However, dirt and dust deposits on the impeller and the motor, particularly in the gap between
the impeller and the inlet nozzle can impair the function of the separately driven fan.
• Remove the dirt and dust deposits regularly; the intervals depend on how dirty the
surrounding area is.
• Carefully clean the bogie wheel. Irregular deposits can result in imbalance.
• The full flowrate is only achieved if the inward flow of air to the impeller is unrestricted.
– There must be a clearance of at least 1 x air intake diameter in the axial direction.
– A uniform gap must be maintained between the impeller and the air intake assembly.
Maintenance
9.2 Inspection and maintenance
1FZ shaft height 280
Operating Instructions, 02/2022, A5E51698698A
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