Omron SYSDRIVE 3G3MV User Manual page 344

Using the Inverter for a Motor
D Vibration
The 3G3MV Series employs high carrier PWM control to reduce motor vibration. When
the motor is operated with the Inverter, motor vibration is almost the same as when oper-
ated 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 constant speed is to
be operated in variable speed mode.
If resonance occurs, install vibration-proof rubber on the motor base.
·Imbalance rotor
Take special care when the motor is operated at a high speed (50 Hz or more).
D Noise
Noise is almost the same as when the motor is operated with a commercial power sup-
ply. Motor noise, however, becomes louder when the motor is operated at a speed
higher than the rated speed (50 Hz).
H Using Inverter for Special Motors
D Pole-changing Motor
The rated input current of pole-changing motors differs from that of standard motors.
Select, therefore, an appropriate Inverter according to the maximum input current of the
motor to be used.
Before changing the number of poles, always make sure that the motor has stopped.
Otherwise, the overvoltage protective or overcurrent protective mechanism will be actu-
ated, resulting in an error.
D Submersible Motor
The rated input current of submersible motors is higher than that of standard motors.
Therefore, always select an Inverter by checking its rated output current.
When the distance between the motor and Inverter is long, use a cable thick enough to
connect the motor and Inverter to prevent motor torque reduction.
D Explosion-proof Motor
When an explosion-proof motor or increased safety-type motor is to be used, it must be
subject to an explosion-proof test in conjunction with the Inverter. This is also applicable
when an existing explosion-proof motor is to be operated with the Inverter.
Chapter 11
11-3