Measurement Of The Insulation Resistance And Polarization Index In The Context Of Maintenance Work; Inspections In The Event Of Faults - Siemens SIMOTICS 1PQ8 Operating Instructions Manual

Risk of explosion due to static charging
If you clean the machine with compressed air, plastic components may become statically
charged and create a potentially explosive atmosphere. An explosion can occur. This can
result in death, serious injury or material damage.
● Do not use compressed air to clean plastic parts in an explosive atmosphere.
● When cleaning the machine, make sure that the air in the vicinity of the machine is free
9.1.2 Measurement of the insulation resistance and polarization index in the context of
maintenance work
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" (Page 51)
9.1.3

Inspections in the event of faults

Natural disasters or unusual operating conditions, such as overloading or short circuit, are
faults that overload the machine electrically or mechanically.
Immediately perform an inspection after such faults.
SIMOTICS TN Series N-compact 1PQ8
Operating Instructions 11/2018
WARNING
of gas and dust.
Maintenance
9.1 Inspection and maintenance
111