Setting procedure of Real sensorless vector
control (speed control)
Perform secure wiring. (Refer to
Set the motor (Pr.71). (Refer to
Set Pr.71 Applied motor to "0" (standard motor) or "1" (constant-torque motor).
Set the overheat protection of the motor (Pr.9). (Refer to
Set the motor capacity and number of motor poles (Pr.80 and Pr.81). (Refer to
V/F control is performed when the setting is "9999" (initial value).
Set the rated motor voltage and the rated motor frequency (Pr.83 and Pr.84). (Refer to
Select the control method (Pr.800). (Refer to
Select Pr.800 = "10" (speed control) or "12" (speed/torque switchover) to enable speed control.
Set the operation command. (Refer to
Select the start command and speed command.
Set the torque limit (Pr.810). (Refer to
Perform the offline auto tuning (Pr.96). (Refer to
Perform the test operation.
• Select online auto tuning (Pr.95). (Refer to
• Perform easy gain tuning. (Refer to
• Adjust the speed control gain manually. (Refer to
• During Real sensorless vector control, offline auto tuning must be performed properly before starting operations.
• The speed command setting range under Real sensorless vector control is 0 to 400 Hz.
• The carrier frequency is limited during Real sensorless vector control. (Refer to
• Torque control is not available in a low-speed (about 10 Hz or lower) regenerative range, or with a low speed and light load
(about 5 Hz or lower and rated torque about 20% or lower). Vector control must be selected.
• Performing pre-excitation (LX signal and X13 signal) under torque control may start the motor running at a low speed even
when the start signal (STF or STR) is not input. The inverter at a start command ON may also rotate the motor at a low speed
even though a speed limit value is set to zero Therefore, confirm that the motor running will not cause any safety problem
before performing pre-excitation.
• Switching between the Forward rotation command (STF) and Reverse rotation command (STR) must not be performed during
operations under torque control. An overcurrent trip (E.OC) or opposite rotation deceleration fault (E.11) will occur.
• When performing continuous operations under Real sensorless vector control in FR-A820-00250(3.7K) or lower or FR-A840-
00126(3.7K) or lower, the speed fluctuation increases when the value is 20 Hz or less, and in the low-speed range of less than
1 Hz, there may be torque shortage. In such case, stop the inverter and restart it to improve the situation.
• In case of starting the motor while the motor is coasting under Real sensorless vector control, the frequency search must be
set for the automatic restart after instantaneous power failure function (Pr.57 ≠ "9999", Pr.162 = "10"). (Refer to
• When Real sensorless vector control is applied, there may not be enough torque provided in the ultra low-speed range of about
2Hz or lower.
Generally, the speed control range is as follows.
For power driving, 1:200 (2, 4 or 6 poles) (available at 0.3 Hz or higher when the rating is 60 Hz), 1:30 (8 or 10 poles) (available
at 60 Hz or higher when the rating is 60 Hz).
For regenerative driving, 1:12 (2 to 10 poles) (available at 5 Hz or higher when the rating is 60 Hz).
5.3 Speed control under Real sensorless vector control, vector control, PM sensorless vector control