Rockwell Automation Liqui-Flo AC GP Vector Drive Version 6.4 - Manual (Page 138)

4-56 LiquiFlo AC Drive, Software Reference Version 6.4
Important: If you set H.003 = 0, you must perform the identification test (using H.020)
prior to running.
Torque boost is required to offset the voltage drop of the AC motor at low speeds. For
high friction loads and high inertia loads, high starting torque may be needed.
Increasing Torque Boost Voltage will increase motor starting torque. See figure 4.11.
If the torque boost voltage setting (H.003) is too high, the motor may draw excessive
starting current, resulting in an OL or PUo fault, or the drive may go into current limit
and not accelerate. When H.003 = 0, the drive automatically provides torque boost
voltage that is a function of motor load. If the motor does not accelerate or a fault
occurs, set parameter H.003 equal to 0.
H.003 Torque Boost Voltage
This parameter sets
the percentage of
output voltage boost
at zero frequency. It
is set as a
percentage of Motor
Nameplate Volts
(H.000). Parameter Range: 0.0% to 20.0% of nominal inverter voltage
Default Setting: 0.5%
Parameter Type: Configurable
Refer also to parameters: H.000 Motor Nameplate Volts
Figure 4.11 – Torque Boost Voltage
100
B a s e F re q u e n cy
V o lta g e
O u tp u t
%
O u tp u t F re q u e n cy
(H z)
0
1
C o n s ta n t
V /H z
R a tio
T o rq u e B o o st
H .0 0 3 = 1 %