● The electronic thermal relay function does not guarantee protection of the motor from
overheating. It is recommended to install both an external thermal and PTC thermistor for
● Do not use a magnetic contactor on the inverter input for frequent starting/stopping of the
inverter. Otherwise, the life of the inverter decreases.
● Use a noise filter to reduce the effect of electromagnetic interference and follow the accepted
EMC procedures for proper installation of frequency inverters. Otherwise nearby electronic
equipment may be affected.
● Take appropriate measures regarding harmonics. Otherwise this can endanger compensa-
tion systems or overload generators.
● When driving a 400V class motor by the inverter, the motor must be an insulation-enhanced
motor or measures must be taken to suppress surge voltage. Surge voltage attributable to
the wiring constants may occur at the motor terminals, deteriorating the insulation of the
● Use a motor designed for inverter operation. (The stress for motor windings is bigger than
in line power supply).
● When parameter clear or all clear is performed, set again the required parameters before
starting operations. Each parameter returns to the initial value.
● The inverter can be easily set for high-speed operation. Before changing its setting, fully
examine the performances of the motor and machine.
● The DC braking function of the frequency inverter is not designed to continuously hold a
load. Use an electro-mechanical holding brake on the motor for this purpose.
● Before running an inverter which had been stored for a long period, always perform inspec-
tion and test operation.
● For prevention of damage due to static electricity, touch nearby metal before touching this
product to eliminate static electricity from your body.
● Only one PM motor can be connected to an inverter.
● A PM motor must be used under PM sensorless vector control. Do not use a synchronous
motor, induction motor, or synchronous induction motor.
● Do not connect a PM motor in the induction motor control settings (initial settings). Do not
use an induction motor in the PM sensorless vector control settings. It will cause a failure.
● In the system with a PM motor, the inverter power must be turned ON before closing the
contacts of the contactor at the output side.
Test operation and adjustment
● Before starting operation, confirm and adjust the parameters. A failure to do so may cause
some machines to make unexpected motions.