Siemens SIMOTICS DP series, Руководство по эксплуатации

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Assembly
5.2 Installing the machine
Standard motors SH 63 ... 355
Operating Instructions, 12/2018, A5E38483075A
49
critical resistance value. Convert the value for the current winding temperature at the time
of measurement, see above table.
Measuring the polarization index
1. To determine the polarization index, measure the insulation resistances after one minute
and ten minutes.
2. Express the measured values as a ratio:
PI =
R
insul 10 min
/
R
insul 1 min
Many measuring devices display these values automatically following the measurement.
For insulation resistances > 5000 M Ω, the measurement of the PI is no longer meaningful
and consequently not included in the assessment.
R
(10 min)
/ R
(1 min)
Assessment
≥ 2 Insulation in good condition
< 2 Dependent on the complete diagnosis of the insulation
NOTICE
Damage to insulation
If the critical insulation resistance is reached or undershot, this can damage the insulation
and cause voltage flashovers.
•
Contact the service center.
•
If the measured value is close to the critical value, you must subsequently check the
insulation resistance at shorter intervals.
Limit values of the anti-condensation heating insulation resistance
The insulation resistance of the anti-condensation heating with respect to the machine
housing should not be lower than 1 M Ω when measured at 500 V DC.
5.2 Installing the machine
5.2.1 Preparing the assembly area
1. Prepare a suitable assembly area (e.g. assembly stands). Make sure that the assembly
area has sufficient clearance from the floor for the DE shaft end. The necessary data is
provided in the machine dimension drawing.
2. Refer to the shipping documents to check that all motor components are available for
assembly.