Contents

Motor Application Precautions
Using the Inverter for an Existing Standard Motor
Observe the following precautions when using an Inverter for an existing standard motor.
•Low Speed Ranges
If a standard cooled motor is used at low speed the cooling effects are diminished. If the motor is used in constant
torque applications in low speed area the motor may overheat. If full torque is required at low speed continuously
an externally cooled motor must be used.
•Installation Withstand Voltage
If the inverter is used with an input voltage of 440 V or higher and long motor cables, voltage spikes at the
motor terminals may occur which can damage the motor windings. Please ensure that the motor insulation
class is sufficient.
•Noise
The noise generated in the motor depends on the carrier frequency. The higher the setting the less the generated
noise is.
Using the Inverter for Special Motors
Observe the following precautions when using a special motor.
•Pole-changing Motor
The rated input current of pole-changing motors differs from that of standard motors. Select an appropriate
Inverter according to the maximum current of the motor.
•Single-phase Motor
Do not use an Inverter for a single-phase capacitor motor. Any capacitors directly connected to the inverter
output may damage the Inverter.
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