Fuji Electric frenic mini series - Precautions for Use

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Precautions for Use
Driving a 460V
general-purpose
motor
When driving a 460V general-purpose motor with an inverter using
extremely long wires, damage to the insulation of the motor may occur. Use
an output circuit filter (OFL) if necessary after checking with the motor
manufacturer. Fuji motors do not require the use of output circuit filters
because of their good insulation.
Torque
characteristics
and temperature
rise
When the inverter is used to run a general-purpose motor, the temperature
of the motor becomes higher than when it is operated using a commercial
power supply. In the low-speed range, the cooling effect will be weakened,
so decrease the output torque of the motor. If constant torque is required in
the low-speed range, use a Fuji inverter motor or a motor equipped with an
externally powered ventilating fan.
Vibration
When an inverter-driven motor is mounted to a machine, resonance may be
caused by the natural frequencies of the machine system.
Note that operation of a 2-pole motor at 60 Hz or higher may cause
abnormal vibration.
* The use of a rubber coupling or vibration dampening rubber is
recommended.
* Use the inverter's jump frequency control feature to skip the resonance
frequency zone(s).
In running
general-
purpose
motors
Noise
When an inverter is used with a general-purpose motor, the motor noise
level is higher than that with a commercial power supply. To reduce noise,
raise carrier frequency of the inverter. Operation at 60 Hz or higher can also
result in higher noise level.
High-speed
motors
If the set frequency is set to 120 Hz or more to drive a high-speed motor,
test-run the combination of the inverter and motor beforehand to check for
safe operation.
Explosion-proof
motors
When driving an explosion-proof motor with an inverter, use a combination
of a motor and an inverter that has been approved in advance.
Submersible
motors and pumps
These motors have a larger rated current than general-purpose motors.
Select an inverter whose rated output current is greater than that of the
motor.
These motors differ from general-purpose motors in thermal characteristics.
Set a low value in the thermal time constant of the motor when setting the
electronic thermal overload protection.
In running
special
motors
Brake motors
For motors equipped with parallel-connected brakes, their braking power
must be supplied from the primary circuit. If the brake power is connected
to the inverter's power output circuit by mistake, the brake will not work.
Do not use inverters for driving motors equipped with series-connected
brakes.