Avoidance Of Damage To Roller Bearings During Stoppages; Measuring The Insulation Resistance After An Extended Stoppage - Siemens SIMOTICS HV M Operating Instructions Manual

8.8.3

Avoidance of damage to roller bearings during stoppages

Extended stoppages at the identical or almost identical resting position of the rotor in the roller
bearings can result in damage, such as brinelling or corrosion.
● During stoppages, regularly start up the machine for a brief period once a month. As a
● During recommissioning, refer to the information in Chapter "Commissioning".
See also
Commissioning (Page 71)
Greasing the roller bearings prior to commissioning (Page 73)
8.8.4

Measuring 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 41)
SIMOTICS HV M 1RN76308PR900CG0-Z
Operating Instructions 07/2018
minimum, turn the rotor several times.
If you have uncoupled the machine from the driven machine and secured the rotor with a
rotor shipping brace, then remove this before turning the rotor over or starting up the
machine.
Make sure that the resting position of the rotor after the rotor has been turned over is
different from its previous position. Use the fitted key or the coupling halves as reference
markers.
Operation
8.8 Stoppages
81