Siemens SIMOTICS FD 1MM1 Series, Operating And Installation Instructions

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● Any supplementary motor monitoring devices and equipment have been correctly
connected and are functioning correctly.
● In continuous operation, the motor cannot exceed the specified upper speed limit n
max
or
undershoot the lower speed limit n
min
.
The permissible acceleration time to the limit speed n
min
depends on the parameter
assignment.
7.2.1 Operation on a converter with a low pulse frequency
WARNING
Risk of explosion as a result of increased motor temperature
If the pulse frequency is less than the rated pulse frequency, then increased motor losses
occur. This results in a higher motor temperature.
An explosion can occur in operation. This can result in death, serious injury or material
damage.
● Observe the data on the machine rating plate.
● Never fall below the minimum pulse frequency. This means that you avoid exceeding the
temperature class, and as a consequence igniting an explosive atmosphere.
WARNING
Dangerous voltage via the converter
As long as the feeding converter is switched on, or the DC link of the converter is not
discharged, there can be a voltage at the motor terminals even when the rotor is not moving.
The voltage is up to 1000 V, depending on the converter type.
Ensure that the five safety rules (Page 15) are followed before working on the motor.
7.3 Measuring the insulation resistance before commissioning
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?
Start-up
7.3 Measuring the insulation resistance before commissioning
SIMOTICS FD 1MM1
Operating Instructions 02/2019
97