Specifications

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19 FX BOOST (FIXED BOOST)
This parameter is used in applications which require high starting torque. FX BOOST
increases the output voltage at lower output frequencies (below 30 Hz for 60 Hz base
frequency), in order to boost the torque capability of the motor. Refer to the diagram below.
The factory default for FX BOOST depends on the horsepower rating of the drive. Refer to
the table below:
The diagram below illustrates how FX BOOST alters the V/Hz ratio to increase motor
torque.
The FX BOOST setting represents the amount of boost at 0 Hz (approximately 15% in the
example below), and as the output frequency approaches 30 Hz, the boost decreases to zero.
Therefore, at 30 Hz and above, the V/Hz ratio returns to its “normal” state.
FX BOOST FACTORY DEFAULT SETTINGS
FACTORY FACTORY
HP DEFAULT HP DEFAULT
0.25 - 1 5.30 % 15 2.20 %
1.5 - 2 4.40 % 20 2.00 %
3 3.60 % 25 1.80 %
5 3.00 % 30 1.60 %
7.5 2.70 % 40 1.20 %
10 2.40 % 50 - 60 0.80 %