Commissioning; Preparations - Siemens 1PH728 Series Operating Instructions Manual

Commissioning

4
4.1

Preparations

Safety instruction
Warning
Only expert persons should be entrusted with work on power installations.
Checking the insulation resistance
Note
There is no need to check the insulation resistance when commissioning. We only
recommend doing so after long storage or shutdown periods.
After long storage or shutdown periods, the insulation resistance of the windings
must be measured to ground with direct voltage.
Caution
Before you begin measuring the insulation resistance, please read the manual of
the insulation resistance meter you are going to use.
Warning
During the measurement, and immediately afterwards, some of the terminals are at
hazardous voltage levels and must not be touched.
Check the supply feeder cables connected, in order to ensure that the line supply
voltage cannot be connected.
Only ever measure the insulation resistance of the winding to the motor enclosure
when the winding temperature is between 20 and 30°C:
SIEMENS AG - Operating Instructions
Three-phase induction motor 1PH728. 4-1