E6581386
E-4
5
1) Increasing torque automatically according to the load
  Set the automatic torque boost = (automatic torque boost+auto-tuning 1)
Automatic torque boost = detects load current in all speed ranges and automatically adjusts voltage output
from inverter. This gives steady torque for stable runs.
Note 1: The same characteristic can be obtained by setting the V/f control mode selection parameter  to 
(automatic torque boost) and  (auto-tuning 1) to . ⇒ Refer to Section 6.19.
Note 2: Setting  to  automatically programs  to .
Note 3: If stable operation cannot be achieved with this setting, set the parameters  (base frequency), 
(base-frequency voltage),  (rated capacity of motor),  (rated current of motor) and 
(rated number of revolutions of motor) as specified on the motor nameplate, and then set  to  and
 to  again.
2)
 
When using vector control (increasing starting torque and high-precision operations)
  Set the automatic torque boost = (sensorless vector control+auto-tuning 1)
Setting automatic torque boost = (Sensorless vector control+auto-tuning 1) provides high starting torque
bringing out the maximum in motor characteristics from the low-speed range. This suppresses changes in motor
speed caused by fluctuations in load to provide high precision operation. This setting is most suitable for transfer and
lifting systems that are operated in speed control mode.
Note 1: The same characteristic can be obtained by setting the V/f control mode selection parameter  to 
(Sensorless vector control) and  (Auto-tuning 1) to . ⇒ Refer to Section 6.19.
Note 2: Setting  to  automatically programs  to .
Note 3: If stable operation cannot be achieved with this setting, set the parameters  (base frequency), 
(base-frequency voltage),  (rated capacity of motor),  (rated current of motor) and 
(rated number of revolutions of motor) as specified on the motor nameplate, and then set  to  and
 to  again.
Q  (automatic torque boost) and  (V/f control mode selection)
Automatic torque boost is the parameter for setting V/f control mode selection () and auto-tuning 1 ()
together. That is why all parameters related to change automatically when  is changed.
Automatically programmed parameters
  
 Disabled (Always  is displayed.) –
Check the programmed
value of . (If  is not
changed, it becomes  (V/f
constant).)
–
 Automatic torque boost+auto-tuning 1  Automatic torque boost
: Executed ( after
execution)
 Sensorless vector control+auto-tuning 1  Sensorless vector control
: Executed ( after
execution)
3) Increasing torque manually (V/f constant control)
The VF-PS1 inverter is set to this control mode by factory default.
This is the setting of constant torque characteristics that are suited for such things as conveyors. It can also be used
to manually increase starting torque.
To return to V/f constant control after changing the  setting:
Set the V/f control mode selection parameter 
=
 (constant torque characteristic).
⇒ Refer to Section 5.6.
Note:If you want to increase torque further, raise the setting value of manual torque boost .
How to set manual torque boost parameter  ⇒ Refer to Section 5.7.
If vector control cannot be programmed....
First read the precautions about vector control in 5.6, 10).
1) If the desired torque cannot be obtained ⇒ Refer to 6.19 selection 3.
2) If auto-tuning error “” appears ⇒ Refer to 13.1 and 6.19 selection 3.