Siemens SIMOTICS M-1PH8 User Manual

5.1.2 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?
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 50)
5.1.3 Testing the insulation resistance and polarization index
WARNING
Hazardous voltage at the terminals
During and immediately after measuring the insulation resistance or the polarization index
(PI) of the stator winding, hazardous voltages may be present at some of the terminals.
Contact with these can result in death, serious injury or material damage.
● If any power cables are connected, check to make sure line supply voltage cannot be
delivered.
● Discharge the winding after measurement until the risk is eliminated, e.g. using the
following measures:
– Connect the terminals with the ground potential until the recharge voltage drops to a
non-hazardous level
– Attach the connection cable.
Measure the insulation resistance
1. Before you begin measuring the insulation resistance, please read the operating manual
for the insulation resistance meter you are going to use.
2. Make sure that no power cables are connected.
Mounting
5.1 Preparing for installation
SIMOTICS M-1PH8 1PH818., 1PH822.
50 Operating Instructions 07/2016

Siemens SIMOTICS M-1PH8 Specifications

General

Brand	Siemens
Model	SIMOTICS M-1PH8
Category	Engine
Language	English