The User Manual of JAC200 Series General Frequency Converter
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3~8: VF relation curve between straight line VF and square VF.
10: VF complete separation mode. In this case, the output frequency of frequency converter is independent
of output voltage, output frequency is determined by frequency source and output voltage is determined by
F3-13 (VF separation voltage source).
VF complete separation mode, generally used for such fields as induction heating, inverter power supply
and torque motor control.
11: VF semi-separation mode
In this situation, V and F are in proportion, but proportional relation is set by power supply F3-13 and the
relation between V and F is also associated with the rated voltage and rated frequency of the motor in Group
F1.
If voltage source input is X (X means a value within 0~100%), the relation between Output Voltage V and
Frequency F of frequency converter is as follows:
V/F=2 * X * (Rated voltage of motor)/ (Rated frequency of motor)
F3-01
Torque boost
Default value
Model dependent
Set range
0.0%:
automatic torque boost
0.1%
～
30%
F3-02
Cut-off frequency of torque
boost
Default value
50.00Hz
Set range
0.00Hz~maximum output frequency
To compensate V/F control low-frequency torque characteristic, the boosting compensation is made for
output voltage of frequency converter in low frequency. However, if torque boost is set to a high value, the
motor may be too hot and the overcurrent of frequency converter may occur.
When load is high but there is not enough starting torque of motor, it is recommended to increase this
parameter. The torque boost may be decreased when load is low.
The frequency converter will be in automatic torque boost when the torque boost is set to 0.0. In this
situation, the frequency converter will calculate torque boost automatically according to stator resistance of
motor and other parameters.
Cut-off frequency for torque boost: With this frequency, the torque boost will be valid. If the frequency
exceeds the set frequency, the torque boost will be invalid. See Fig. 6-3 for more information.
