Specifications

Chapter 6 Setting up parameters
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[Tune mode]
Feed forward gain (position mode)
● Function
In the position mode the HA-655 driver controls the error
count, the difference between [command pulse] and
[feedback pulse], to be [0]. At the beginning of inputting a
command pulse train, the actuator starts slowly because
of a of small error count.
The [feed forward] function may accelerate the actuator as
much as possible, adding the speed commands to the
speed control loop. The speed commands are converted
from a command pulse frequency (feed forward rate =
100%). The feed forward function provides acceleration
control, minimizing the position error. The effects of the
feed forward are disabled when the feed forward rate
equals 0%.
The relation between the gain and actuator motion is as follows:
Excessive gain causes mechanical shock and hunting.
● Details of display
1st digit: [3:Feed forward gain]
2nd to 3rd digit: No indication
4th to 6th digit: indicates current [Feed forward gain]. A value from [0] to [100] can be set.
● Operations
(1) To change a value, press the [ADJ] key at least 0.1 second.
⇒1st digit [3] flashes. You can change the value.
(2) When the actuator does hunting or mechanical shock occurs, press the [DOWN] key and set a
lower value. When the position following to command is poor, press the [UP] key to set a higher
value.
(3) To define the new value, press the [SET] key at least 0.1 second.
⇒ Flashing of 1st digit [3] stops and the new value is defined.
(4) To cancel a change in operation, press the [ADJ] key at least 0.1 second.
⇒Flashing of 1st digit [3] stops and the previous value becomes effective.
● Related functions
[Speed loop gain]: [tune mode]→[0:Speed loop gain]
[Speed loop integral compensation]: [tune mode]→[1:Speed loop integral compensation]
[Position loop gain]: [tune mode]→[2:Position loop gain]
HA-655
Command＋
Position
control
FHA
Feedback pulse
−
Error pulse
Feed forward
D O W N U P A D J S E T
Feed forward
Feed forward rate
unit:％
1st digit 6th digit