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For a winding temperature of approx. 25° C, the minimum insulation resistances are 20 MΩ
(U ≤ 1000 V) or 300 MΩ (U > 1000 V). The values apply for the complete winding to ground.
Twice the minimum values apply to the measurement of individual assemblies.
● Dry, new windings have an insulation resistance of between 100 and 2000 MΩ, or possibly
even higher values. An insulation resistance value close to the minimum value could be
due to moisture and/or dirt accumulation. The size of the winding, the rated voltage and
other characteristics affect the insulation resistance and may need to be taken into account
when determining measures.
● Over its operating lifetime, the motor winding insulation resistance can drop due to ambient
and operational influences. Calculate the critical insulation resistance value depending on
the rated voltage by multiplying the rated voltage (kV) by the specific 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 MΩ, 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 (Page 131).
● 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 MΩ when measured at 500 V DC.
Mounting
5.1 Preparing for installation
SIMOTICS M-1PH8 1PH818., 1PH822.
52
Operating Instructions 07/2016
Содержание 1PH818
Страница 2: ...18 07 2016 14 04 V14 00 ...
Страница 12: ...Introduction SIMOTICS M 1PH8 1PH818 1PH822 12 Operating Instructions 07 2016 ...
Страница 28: ...Description SIMOTICS M 1PH8 1PH818 1PH822 28 Operating Instructions 07 2016 ...
Страница 48: ...Preparations for use 4 14 Converter operation SIMOTICS M 1PH8 1PH818 1PH822 48 Operating Instructions 07 2016 ...
Страница 82: ...Electrical connection 6 4 Auxiliary circuits SIMOTICS M 1PH8 1PH818 1PH822 82 Operating Instructions 07 2016 ...
Страница 100: ...Operation 8 10 Faults SIMOTICS M 1PH8 1PH818 1PH822 100 Operating Instructions 07 2016 ...
Страница 126: ...Spare parts 10 9 Speed encoder type 1PH818 1PH822 SIMOTICS M 1PH8 1PH818 1PH822 126 Operating Instructions 07 2016 ...
Страница 136: ...Quality documents SIMOTICS M 1PH8 1PH818 1PH822 136 Operating Instructions 07 2016 ...
Страница 163: ...D 3 Operating instructions of the EC external fan SIMOTICS M 1PH8 1PH818 1PH822 Operating Instructions 07 2016 163 ...
Страница 197: ...AA Manual STROMAG Break AC Manual Ziehl Abegg external fan ...
Страница 198: ...Siemens AG Process Industries and Drives Postfach 48 48 90026 NÜRNBERG GERMANY www siemens com drives ...