Control Modes Of The Vf-P7 Inverter - Toshiba TOSVERT VF-P7 Instruction Manual

3.1 Control modes of the VF-P7 inverter

[Speed control mode] : The motor runs at the speed specified by a frequency
(1) V/f control - V/f constant (constant torque characteristic) ... [default setting]
For loads, such as belt conveyors and cranes, that require, even in low speed ranges, the
same torque as that produced at their respective rated speeds.
(2) V/f control - Square reduction torque
For loads, such as fans, pumps and blowers, the torque of which are proportional to the
squares of their respective rotating speeds.
(3) Automatic torque boost mode.
In this mode, the inverter automatically adjusts the supply voltage to ensure that the motor
produces constant torque in any speed range.
(4) Sensor-less vector control mode,
In this mode, the inverter controls the motor so that it produces sufficiently large torque
even in an extremely low speed range and it keeps its rotating speed constant even if the
load torque fluctuates. This mode of operation is best suited to transportation, lifting and
winding equipment.
(5) Automatic energy-saving mode.
In this mode, the inverter monitors the output voltage and passes an output current
commensurate with the load. This mode of operation is used in conjunction with the above
mode (3) or (4).
[Torque control mode] :
■Sensor vector control (Optional)
When combined with a sensor-equipped motor, the inverter controls the motor with a
higher accuracy.
[Speed control mode] :
[Torque control mode] :
[Position command mode] : Positioning control is carried out by means of pulses.
■Pre-operation check the following check again before starting operation
Pre-operation check the following check again before starting operation.
1) Are all wires and cables connected correctly?
2) Does the supply voltage agree with the rated input voltage?
command.
The motor torque is controlled by torque command signals.
The motor's rotating speed is determined by the
relationship between the load torque and the torque
produced by the motor.
The motor's rotating speed is controlled with a higher
accuracy, even in low speed ranges, by feedback
signals.
The motor torque can be controlled in this mode. The
motor speed is determined by the relation ship between
the load torque and the motor torque. The accuracy in
controlling regenerative torque and power-running
torque at extremely low speeds is improved by feedback
signals.
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