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

Explosion hazard
If the anti-condensation heating is switched on directly after the machine is switched off, the
temperature class or the maximum surface temperature of the machine can be exceeded.
In an explosive atmosphere, there is a risk of an explosion. This can result in death, serious
injury or material damage.
● Only switch on the anti-condensation heating after the motor has been switched off.
8.6.2

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 69)
8.6.3

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?
SIMOTICS HV C 1NB1402-2AA84-4CA0-Z
Operating Instructions 06/2018
WARNING
Carefully comply with the data on the anti-condensation heating plate.
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
8.6 Stoppages
79