Torque Boost Setting (A041/A241,A042/A242, A043/A243,H003/H203,B H004/H204) - Hitachi NES1-004SB Quick Reference Manual

Chapter 7 Explanation of Functions
7.5.2 Torque boost setting
The torque boost setting function allows you to compensate for the voltage drop due to wiring and the
primary resistance of the motor so as to improve the motor torque at low speeds.
When you select automatic torque boost by the torque boost selection (A041/A241), adjust the settings of
the motor capacity selection (H003/H203) and motor pole selection (H004/H204) based on the motor to be
driven.
Item
Torque boost selection
Manual torque boost value
Manual torque boost frequency
adjustment
Motor capacity
Motor poles setting
Voltage compensation gain
setting for automatic torque
boost
Slippage compensation gain
setting for automatic torque
boost
(1) Manual torque boost
The inverter outputs the voltage according to the settings of the manual torque boost (A042/A242) and
manual torque boost frequency adjustment (A043/A243).
Use the manual torque boost value (A042/A242) to specify the rate of the boost to the voltage (100%) set
by the AVR voltage select.
When increasing the value of the manual torque boost value, be careful to prevent motor over-excitation.
Over-excitation may result in motor burnout.
Use the manual torque boost frequency adjustment (A043/A243) to specify the rate of the frequency at
each breakpoint to the base frequency (100%).
To switch the settings among the 1st and 2nd settings ("A041 to A043" and "A241 to A243"), assign
function "08" (SET) to intelligent input terminals. Use the SET signal for switching.
Output voltage (%)
Function code
A041/A241
A042/A242
A043/A243
H003/H203
H004/H204
A046/A246
A047/A247
100
A042/A242
A043/A243
Data or range of data
00
01
0.0 to 20.0(%)
0.0 to 50.0(%)
0.1 to 5.5(kW)
2, 4, 6, 8 (poles)
0. to 255.
0. to 255.
Base frequency Output
(100%) frequency
7 - 22
Description
Manual torque boost
Automatic torque boost
Setting of the rate of the boost to
the AVR voltage (A082/A282)
Setting of the rate of the frequency
at breakpoint to the base frequency
(A003/A203)
Selection of the motor capacity
Selection of the number of poles of
the motor
See Item (2), "Automatic torque
boost."
See Item (2), "Automatic torque
boost."