Siemens SIMOTICS XP 1MD4, Инструкция по эксплуатации и монтажу, Страница: 81 / 128

Keep these surfaces clean and protect them against corrosion by applying a thin coating of
grease. It is not permissible that any seals are fitted between the surfaces that guarantee that
flame is not transmitted.
9.1.7.2 Explosion hazard due to increased surface temperature
WARNING
Explosion hazard
Components within the motor may be hotter than the maximum permissible surface
temperature for the enclosure. In an explosive atmosphere, dust can ignite and an explosion
occur. This can result in death, serious injury or material damage.
● Do not open the motor in an explosive and dusty atmosphere when it is still at normal
operating temperature.
● Allow the machine to cool down before opening it.
9.1.7.3 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
SIMOTICS XP 1MD4/1MD5
Operating Instructions 05/2015
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