INVT GD300-004G-4, Operation Manual

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Goodrive300 inverters Basic operation instruction
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For the load of constant torque, such as the conveyor belt which runs linearly. It is properly to
select linear V/F curve because it needs constant torque.
For the load of decreasing torque, such as fans and water pumps, it is properly to select
corresponding 1.3th, 1.7th or 2th power of V/F curve because the actual torque is 2-squared or
3-squared of the rotating speed.
Goodrive300 series inverters provide multi-dots V/F curve, the user can change the output V/F
curve by setting the voltage and frequency of three middle dots. The whole curve is comsisted of
5 dots. The starting dot is (0Hz, 0V), and the ending dot is (the basic frequency of the motor, the
rated voltage of the motor). During the setting processing: 0≤f
1
≤f
2
≤f
3
≤the basic frequency of the
motor; 0≤V
1
≤V
2
≤V
3
≤the rated voltage of the motor.
Goodrive300 series inverters provide special function code for V/F control mode which can
improve the performance of V/F control by means of setting.
1. Torque boost
Torque boost function can compensate the performance of low speed torque during V/F control.
The inverter will adjust the torque boost according to the actual load.
Note:
The torque boost takes effect only when the frequency is under the cap frequency of the boost.
If the torque boost is too big, low frequency vibration or overcurrent fault may occur. Please lower
the torque boost.