Operation selection at power failure and instantaneous power failure
Frequency search gain (Pr. 298), offline auto tuning (Pr. 96)
When automatic restart after instantaneous power failure operation (with frequency search) is valid at V/F control, perform
offline auto tuning.
Perform offline auto tuning during V/F control in the following order to set Pr. 298 Frequency search gain automatically.
(Refer to page 120 during Advanced magnetic flux vector control and General-purpose magnetic flux vector control.)
Before performing offline auto tuning
Check the following before performing offline auto tuning.
The inverter is under V/F control
A motor should be connected. Note that the motor should be at a stop at a tuning start.
The motor capacity should be equal to or one rank lower than the inverter capacity. (note that the capacity is 0.1kW or
A high-slip motor, high-speed motor and special motor cannot be tuned. (The maximum frequency is 120Hz.)
Even if tuning is performed without motor running (Pr. 96 Auto tuning setting/status = "21"), the motor may run slightly.
Therefore, fix the motor securely with a mechanical brake, or before tuning, make sure that there will be no problem in
safety if the motor runs (caution is required especially in vertical lift applications). Note that tuning performance is
unaffected even if the motor runs slightly.
Offline auto tuning will not be performed properly if it is performed with a surge voltage suppression filter (FR-ASF-H, FR-
BMF-H) connected between the inverter and motor. Remove it before starting tuning.
1) Set "21" in Pr. 96 Auto tuning setting/status.
Tuning is performed without motor running.
It takes approximately 9s ∗ until tuning is completed.
(Excitation noise is produced during tuning.)
∗Tuning time differs according to the inverter capacity and motor type.
2) Set the rated motor current (initial value is rated inverter current) in Pr. 9 Electronic thermal O/L relay. (Refer to page 116)
3) Set Pr. 71 Applied motor according to the motor used.
Mitsubishi standard motor
Mitsubishi high efficiency motor
Other manufacturer's standard
Other manufacturer's constant
∗1Refer to page 118, for other settings of Pr. 71.
Execution of tuning
Before performing tuning, check the monitor display of the operation panel or parameter unit (FR-PU04/FR-PU07) if the
inverter is in the status for tuning. (Refer to 2) below)
1) When performing PU operation, press
For External operation, turn ON the start command (STF signal or STR signal). Tuning starts.
SF-JR 4P 1.5kW or less
Others (SF-JRC, etc.)
of the operation panel.
Pr.71 Setting ∗1