• When the wiring length between the inverter and the motor is long (30 m or longer as a reference), use the offline auto tuning
function to drive the motor in the optimum operation characteristic.
• Tuning is enabled even when a load is connected to the motor.
• Reading/writing of the motor constants tuned by offline auto tuning are enabled. The offline auto tuning data (motor constants)
can be copied to another inverter using the operation panel.
• The offline auto tuning status can be monitored with the operation panel or the parameter unit.
Before performing offline auto tuning
Check the following points before performing offline auto tuning:
• A value other than "9999" is set in
• A motor is connected. (Check that the motor is not rotated by an external force during tuning.)
• Select a motor with the rated current equal to or less than the inverter rated current. (The motor capacity must be 0.4 kW
or higher.) If a motor with substantially low rated current compared with the inverter rated current, however, is used, speed
and torque accuracies may deteriorate due to torque ripples, etc. Set the rated motor current to about 40% or higher of the
inverter rated current.
• Tuning is not available for a high-slip motor, high-speed motor, or special motor.
• The maximum frequency is 400 Hz.
• The motor may rotate slightly even if the offline auto tuning without motor rotation (
selected. (The slight motor rotation does not affect the tuning performance.)
Fix the motor securely with a mechanical brake, or before tuning, make sure that it is safe even if the motor rotates.
(Caution is required especially in vertical lift applications.)
• Offline auto tuning is not performed correctly when the surge voltage suppression filter (FR-ASF-H/FR-BMF-H) is inserted
between the inverter and motor. Be sure to remove it before performing tuning.
• To perform tuning, set the following parameters about the motor.
Electronic thermal O/L
Auto tuning setting/
• Before performing tuning, check the monitor display of the operation panel or parameter unit if the inverter is in the state ready
for tuning. The motor starts by turning ON the start command while tuning is unavailable
• In the PU operation mode, press
For External operation, turn ON the start command (STF signal or STR signal). Tuning starts.
• Satisfy the required inverter start conditions to start offline auto tuning. For example, stop the input of the MRS signal.
• To force tuning to end, use the MRS or RES signal or press
(Turning the start signal (STF signal or STR signal) OFF also ends tuning.)
• During offline auto tuning, only the following I/O signals are valid. (initial value).
Input terminal: STF, STR
Output terminal: ABC
5.9 (C) Motor constant parameters
, and General-purpose magnetic flux vector control is selected.
9999 (V/F control)
Set the motor capacity (kW).
Inverter rated current
Set the rated motor current (A).
0 (standard motor)
Set this parameter according to the motor.
1: Tuning is performed without rotating the motor. (Excitation noise occurs at this
on the operation panel.
Pr.96 Auto tuning setting/status
on the operation panel.
= "1") is