Motor Application Precautions; Using The Inverter For An Existing Standard Motor - Omron I537-E2-01 User Manual

Motor Application Precautions

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Using the Inverter for an Existing Standard Motor

When a standard motor is operated by the Inverter, power loss is slightly higher than when operated by a com-
mercial power supply. Observe the following precautions when using an Inverter for an existing standard
motor.
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Low Speed Range
Cooling effects diminish in the low-speed range, resulting in an increase in the motor temperature. Therefore,
the motor torque should be reduced in the low-speed range whenever using a motor not mabe by OMRON. If
100% torque is required continuously at low speed, consider using a special inverter or vector motor.
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Installation Withstand Voltage
If the input voltage is high (440 V or higher) or the wiring distance is long, the motor insulation voltage must
be considered. Contact your OMRON representative for details.
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High-speed Operation
When using the motor at a high speed (50 Hz or more), problems may arise in dynamic balance and bearing
durability. Contact your OMRON representative for details.
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Torque Characteristics
The motor may require more acceleration torque when the motor is operated with the Inverter than when oper-
ated with a commercial power supply. Check the load torque characteristics of the machine to be used with the
motor to set a proper V/f pattern.
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Vibration
The Inverter uses a high carrier PWM to reduce motor vibration. (A parameter can be set to select low carrier,
PWM modulation control as well.) When the motor is operated with the Inverter, motor vibration is almost the
same as when operated with a commercial power supply.
Motor vibration may, however, become greater in the following cases.
Resonance with the Natural Frequency of the Mechanical System
Take special care when a machine that has been operated at a parameter speed is to be operated in variable
speed mode. If resonance occurs, install vibration-proof rubber on the motor base or use the frequency jump
function to skip any frequency resonating the machine.
Imbalanced Rotor
Take special care when the motor is operated at a higher speed (50 Hz or more).
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Noise
Noise varies with the carrier frequency. At high carrier frequencies, the noise is almost the same when the
motor is operated with a commercial power supply. Motor noise, however, becomes louder when the motor is
operated at a speed higher than the rated speed (50 Hz).
Motor Application Precautions
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