Hitachi X200 Series - Manual (Page 91)

Be aware that running the motor at a low speed for a long time can cause motor
overheating. This is particularly true when manual torque boost is ON, or if the motor
relies on a built-in fan for cooling.
NOTE: Manual torque boost applies only to constant torque (A044=00) and variable
torque (A044=01) V/f control.
Voltage gain – Using parameter A045 you can
modify the voltage gain of the inverter (see
graph at right). This is specified as a
percentage of the full scale output voltage.
The gain can be set from 20% to 100%. It
should be adjusted in accordance with the
motor specifications.
The following table shows the methods of
torque control selection.
“A” Function Defaults
Func.
Code
Name /
SRW Display
Description
Run
Mode
Edit
-FE
(EU)
-FU
(USA)
Units
Torque boost select A041
V-Bst Slct MN
U 00 00 %
Torque boost select, 2 nd motor A241
2VBst Slct MN
Two options:
00
…Manual torque boost
01 …Automatic torque boost
U 00 00 %
Manual torque boost value A042
V-Bst V 0005.0%
9 1.8 1.8 %
Manual torque boost value,
2 nd motor
A242
2VBst V 0005.0%
Can set boost starting torque
between 0 and 20% above normal
V/f curve,
range is 0.0 to 20.0% 9 0.0 0.0 %
Manual torque boost
frequency adjustment A043
M-Bst F 0003.0%
9 10.0 10.0 %
Manual torque boost
frequency adjustment,
2nd motor
A243
2MBst F 0000.0%
Sets the frequency of the V/f
breakpoint A in graph (top of
previous page) for torque boost,
range is 0.0 to 50.0%
9 0.0 0.0 %
V/f characteristic curve A044
CTRL C-TRQ
U 00 00 −
V/f characteristic curve,
2nd motor
A244
2CTRL C-TRQ
Two available V/f curves;
00
…Constant torque
01 …Reduced torque
06 …Reduced torque1 U 00 00 −
V/f gain setting A045
V-Gain 00100%
9 100. 100. %
V/f gain setting,
2nd motor
A245
2V-Gain 00100%
Sets voltage gain of the inverter,
range is 20. to 100.%
9 100. 100. %
100%
fbase fmax
A045=100
80%
A045=80
V
0
3−17
Confi
guri
ng Driv
e
Parameters