Specifications

Chapter 6 Setting up parameters
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6-5-2 Functions of the tune mode
Speed loop gain (position / speed mode)
● Function
The HA-655 drivers make actuators follow command
signals precisely by triple feedback loops of position,
speed, and current. The [speed loop gain] adjusts the
proportional gain of the speed feedback loop. The relation
between the gain and actuator motion is as follows:
High gain ⇒ obtains high servo stiffness and high
response.
Excessive gain makes the servo system
unstable, hunting, and a tendency to
overshoot.
Low gain ⇒ Inadequate gain makes the servo system
subject to undershooting.
Set the highest gain within the limits of no hunting, no overshooting nor undershooting by a step
command.
● Details of display
1st digit: [0: speed loop gain]
2nd to 6th digit: Indicates the current [speed loop gain]. An integer from [1] to [9999] can be set.
● Operations
(1) To change a value, press the [ADJ] key at least 0.1 second.
⇒1st digit [0] flashes. You can change the value.
(2) If the actuator is hunting or takes a long time for its speed to settle after a step command, then
press the [DOWN] key to set a lower level.
If the actuator takes a long time for its speed after a step command, then press the [UP] key to set
a higher level.
(3) To define the new value, press the [SET] key at least 0.1 second.
⇒ Flashing of 1st digit [0] 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 [0] stops and the previous value is restored.
● Related functions
[Speed loop integral compensation]: [tune mode]→[1: Speed loop integral compensation]
[Position loop gain]: [tune mode]→[2:position loop gain]
[Feed forward gain]: [tune mode]→[3:Feed forward gain]
D O W N U P A D J S E T
Speed loop gain
Indicates current speed loop gain.
Overshoot
Best
Undershoot
Speed
Time
1st digit 6th digit