Maintenance
9.2 Inspection and maintenance
1LE7 shaft heights 71 ... 315
96
Operating Instructions, 04/2022, A5E51689275A-AA
9.2.10
Drain condensate
If there are condensation drain holes present, open these at regular intervals, depending on
climatic conditions.
WARNING
Hazardous voltage
The winding can be damaged if objects are introduced into the condensation holes
(optional). This can lead to death, serious injury or material damage.
Note the following to maintain the degree of protection:
•
Switch off the motor so that it is in a no-voltage condition before you open the
condensation drain holes.
•
Close the condensation drain holes, e.g. using T-plugs, before commissioning the motor.
NOTICE
Reduction of the degree of protection
If condensation drain holes are not closed, then this can result in material damage to the
motor.
In order to maintain the degree of protection, after the condensation has been drained, you
must close all of the drain holes.
9.2.11
Insulation resistance and polarization index
Measuring the insulation resistance and polarization index (PI) provides information on the
condition of the motor. It is therefore important to check the insulation resistance and the
polarization index at the following times:
•
Before starting up a motor 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 motor needs commissioning or any necessary
measures such as cleaning and/or drying the winding:
•
Can the motor be put into operation?
•
Must the windings be cleaned or dried?
Detailed information on testing and the limit values can be found here:
Checking the insulation resistance (Page 45)
