Siemens SIMOTICS XP 1MB155, Operating Instructions Manual

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Maintenance
9.1 Inspection and maintenance
1MB155 / 1MB555
Operating Instructions, 03/2018, A5E41926185A
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9.1.9 Maintenance
9.1.9.1 Explosion protection for machines with type of protection "Ex d"
For explosion-protected machines with type of protection "Ex d" or "Ex db" in accordance
with IEC / EN 60079–0 and IEC / EN 60079–1, observe the following:
● Machined bearing and fitting surfaces on the following components must not be reworked
or painted:
–
Stator frame
– End shields, bearing cover
– Motor shaft
– Gland plate
– Terminal box lower part, terminal box cover
– Gland plates for additional terminal boxes, where present
● 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.
9.1.9.2 Explosion hazard due to increased surface temperature
WARNING
Explosion hazard due to increased surface temperature
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.
9.1.9.3 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