E6581158
E-19
5
3) Increasing starting torque
Setting of V/F control mode selection
RV
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.
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Automatically
adjusts the
amountof torque
boost
O
u
tput
v
o
lt
age(
%)
Base frequency
voltage
XNX
Output frequency
(Hz)
Base frequency
XN
0
Note:
This control system can oscillate and destabilize runs depending on the load. If that should
happen, set V/F control mode selection
RV
to
(V/F constant) and increase torque manu-
ally.
+
Motor constant must be set
If the motor you are using is a 4P Toshiba standard motor and if it has the same capacity as the inverter,
there is basically no need to set the motor constant. In any other case, be sure to set the parameters
H
to
H
properly.
Be sure to set
H
(rated current of motor) and
H
(rated speed of motor) correctly, as specified on
the motor’s nameplate. For the setting of
H
(no-load current of motor), refer to the motor test report.
There are three procedures for setting the other motor constants.
1) Auto torque boost and a motor constant (auto-tuning) can be set at once.
To do so, set the basic parameter
CW
to
.
⇒
For details, see 1 in 5.2.
2) The motor constant can be automatically set (auto-tuning). Set the extended parameter
H
to
.
⇒
For details, see selection 2 in 6.17.
3) Each motor constant can be set individually.
⇒
For details, see selection 3 in 6.17.
4) Vector control - increasing starting torque and achieving high-precision operation.
Setting of V/F control
RV
to
(Vector control)
Using sensor-less vector control with a Toshiba standard motor 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.
