Insulation Resistance; Insulation Resistance And Polarization Index - Siemens SIMOTICS A 1FU9 Operating Instructions Manual

NOTICE
Damage to the motor
To avoid material damage, before commissioning, check whether the correct direction of
rotation of the machine has been set on the customer side, e.g. by decoupling from the driven
load.
Damage to mounted parts and components as a result of high temperatures
The motor components get very hot during operation. High temperatures can damage parts
mounted by customers, such as cables manufactured out of materials that are not heat resistant.
• Temperature-sensitive parts must not come into contact with or be attached to components
mounted on the machine.
• Only use heat-resistant mounting parts. The connecting cables and cable entries must be
suitable for the particular application.
6.3.3

Insulation resistance

6.3.3.1

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
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?
From this, 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 56)
1FU9
Operating Instructions, 10/2023, A5E46712792A
Assembly
6.3 Preparing for installation
55