Siemens SIMOTICS FD 1LH1, Operating Instructions & Installation Instructions

Page: 115 / 174

8.4.4 Measurement of the insulation resistance after an extended stoppage
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 55)
8.5 Decommissioning the machine
NOTICE
Damage as a result of an extended period out of service
If the machine is going to be out of service for longer than six months, then take the necessary
measures for preservation and storing. Otherwise damage to the machine will result.
Record the decommissioning steps. This log will be useful upon recommissioning.
8.6 Switching off the water-cooling system
● Switch off the water-cooling system after switching off the machine. Condensation can form
inside the machine if cooling water flows while the machine is at a standstill.
● Only switch off the water cooling system once the machine has cooled down. This will
prevent the accumulation of residual heat.
8.7 Draining the coolant
If you take the machine out of service, drain the coolant if this is necessary for the ambient
conditions.
Operation
8.5 Decommissioning the machine
SIMOTICS FD 1LH1
Operating Instructions 01/2019
115