Toshiba VF-A7 Welding System User Manual


 
E-3
5.2 Increasing starting torque/ energy-saving operation mode
 Automatic V/f mode setting
Title Function Adjustment range Default setting

Automatic V/f
mode setting
: ( is always displayed.)
: Automatic torque boost + auto-tuning
:
Sensorless vector control (speed) + auto-tuning
: Automatic energy-saving + auto-tuning
Note) The parameter always returns to after completion of the setting. To check the setting
(set value), check the
 previous monitor in monitor mode. (Refer to 8.1 for details.)
To automatically increase the torque according to the load condition
Set the automatic V/f mode setting  at (automatic torque boost + auto-tuning).
When the automatic V/f mode setting  is set at (automatic torque boost + auto-tuning),
the load current is observed in all speed ranges and the inverter's output voltage is adjusted
automatically so that the motor can always produce torque large enough for stable operation.
Note1) The same characteristic can be obtained by setting the motor control mode selection
Parameter
 at (automatic torque boost) and the automatic tuning  (auto-
tuning) at . => Refer to 5.10 for details.
[Setting procedure]
Key operated LED display Operation

The running frequency is displayed. (Make this setting When the
motor is out of operation.)(If the monitor display selection
parameter
 is set at [Running frequency])

Press the [MON]key to read the first basic parameter 
(Automatic acceleration/deceleration).

Switch to the parameter  (automatic control) by pressing
the key.
Press the Enter key to display the parameter setting (set value).
Change the parameter setting to (automatic torque boost +
auto-tuning) by pressing the key.

Press the Enter key to save the change. Then,  and the
set value are displayed alternately.
Note 2) Setting  at causes  to be set at automatically.
Function
This parameter enables the inverter to automatically switch V/f control modes and set the
motor constant (online automatic control) at the same time to make the motor produce
larger torque. With this parameter, two control modes can be set at a time, for example,
special V/f control modes, including the automatic torque boost mode and the vecto
r
control mode.
Constant torque characteristic (Default setting)
Automatic torque boost + auto-tuning
Vector control (speed control) + auto-tuning
Automatic energy-saving + auto-tuning
Note) With the motor control selection parameter , you can set the square
reduction torque, the sensor vector control (optional), etc.
=> Refer to 5.10 for details.
MON
ENT
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