Toshiba Tosvert VF-S15 Instruction Manual page 133

3) Increasing starting torque
Setting of V/F control mode selection  to  (automatic torque boost control)
Detects load current in all speed ranges and automatically adjusts voltage output (torque boost) from inverter.
This gives steady torque for stable runs.
Base frequency voltage
:Automatically
adjusts the
amountof torque
boost.
Note: This control system can oscillate and destabilize runs depending on the load. In this case, set
V/F mode selection = (V/F constant) and increase manual torque boost .
● Motor constant must be set
If the motor you are using is a 4P Toshiba standard motor which has the same capacity as the inverter, there
is basically no need to set the motor constant. There are three setting methods as mentioned below. In any
method, set the following parameters according to the motor's name plate.
 (Base frequency 1),  (Base frequency voltage 1),  (Motor rated capacity),  (Motor
rated current),  (Motor rated speed)
1) Simultaneous setting of auto torque boost and auto-tuning (f400=2)
Set the basic parameter  (Torque boost setting macro function) to .
 Refer to section 6.1.5 for details.
2) Automatic setting
Set the extended parameter  (auto-tuning) to .
3) Manual setting
Set each motor constant.  Refer to section 6.25 selection 4 for details.
4) Vector control - increasing starting torque and achieving high-precision operation.
Setting of V/F control mode selection  to 3 (Vector control)
Using sensorless vector control will provide the highest torque at the low speed ranges.
(1) Provides large starting torque.
(2) Effective when stable operation is required to move smoothly up from the low speeds.
(3) Effective in elimination of load fluctuations caused by motor slippage.
● Motor constant must be set
If the motor you are using is a 4P Toshiba standard motor which has the same capacity as the inverter, there
is basically no need to set the motor constant. There are three setting methods as mentioned below. In any
method, set the following parameters according to the motor's name plate.
 (Base frequency 1),  (Base frequency voltage 1),  (Motor rated capacity),  (Motor
rated current),  (Motor rated speed)

0
Base frequency 
F-21
Output frequency (Hz)
 Refer to section 6.25 selection 2 for details.
E6582175
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