Instruction manual

8-3
8.3 Torque Boost (F09, Default 0.1)
IMPORTANT: PARAMETER IS REQUIRED TO BE CHANGED FOR CONSTANT TORQUE APPLICATIONS.
This parameter sets the relationship between output frequency and output voltage. Constant torque applications have
the same torque requirements at low speed as well as at high speed.
See parameter F37 to select Load Selection / Auto Torque Boost.
Initial Setup
For variable Torque / Low Duty applications set parameter F09 to an initial value of 1.0.
For Constant Torque / Medium Duty applications set parameter F09 to an initial value of 2.0.
This parameter sets the torque boost for motor 1.
Setting range: 0.0 to 20.0
To set parameter F09:
- Press PRG key, next select QUICK SET or DATA SET with UP/DOWN and keys and press the
FUNC/DATA key.
- In the parameter list move cursor to F09 with UP/DOWN keys and press FUNC/DATA key to select.
Setting range
Characteristics selected
0.0
Automatic torque boost characteristic where the torque boost value of a constant torque load (a linear
change) is automatically adjusted.
The motor tuning (P04 / A13) should be set to "2" for this function to be valid.
0.1 to 0.9
Square law reduction torque for fan and pump loads.
1.0 to 1.9
Proportional torque for middle duty loads between square law reduction torque and constant torque
(linear change).
2.0 to 20.0
Constant torque (linear change).
Warning: A larger than required torque boost value creates over-excitation at low speeds, continued
operation may cause the motor to overheat. Check the characteristics of the motor for additional
information.
F09
Torque Boost