DM422 Digital Stepping Drive Manual V1.0
Toll Free 1-855-435-4958
26
fraction of the motor's available torque – thereby wasting performance. Furthermore, at mid-range
velocities, the resonance can become so severe that the motor looses synchronization and stalls. The
DM422 driver provides robust anti-resonance control to stop the vibrations and maintain equilibrium.
This feature requires that the driver be configured with respect to the total inertia in the system. If set
improperly, the effectiveness of the feature may be diminished.
The user can invoke or disable the feature by setting
Amp
and
Phase
values in
SystemConfig
window.
Amp
and
Phase
values all zero is to disable the feature, otherwise is to invoke the feature. It
should be enabled unless the system configuration either does not need it or cannot tolerate it. A
system with loose couplings or viscous loading generally does not need this feature. If a system has
compliant (springy) coupling and is absent appreciably viscosity, it may not respond well to the active,
anti-resonant loop in the drive. The anti-resonant feature is not designed to damp such a 4
th
order
system. If the application of anti-resonance results in degradation or instability, it should be disabled.
1
st
ResonanceArea: Parameters for 1
st
resonance area.
It is usually between 0.6rps and 1.2rps.
Amp1
is Amplitude adjustment for 1
st
resonance area.
Phase1
is Phase adjustment for 1
st
resonance area. The user can enter a value directly in the text box
or move the slider bar back and forth to get an optimum value.
2
nd
ResonanceArea: Parameters for 2
nd
resonance area.
It is usually between 1.2rps and 2.4rps.
Default
Amp2
and
Phase2
values are zero.
3
rd
ResonanceArea: Parameters for 3
rd
resonance area.
It is usually between 2.4rps and 4.8rps.
Default
Amp3
and
Phase3
values are 128.
Internal Pluser( Pulse Generator)
The internal pulse generator offers a simple motion control for self-test and anti-resonance tuning. The
user can adjust moving velocity, configure the direction and repeats of the motion.
Bidirectional
: Click the check box to make the motion be bidirectional. Otherwise the motor only run
in one direction.
Positive
: It is used to change the initial direction for the motion.
DM422 Digital Stepping Drive Manual V1.0
Toll Free 1-855-435-4958
27
Interval
: Stop time before the next motion repeat. Unit: ms.
Repeats
: Motion repeat times. If it is bidirectional, one repeat is moving forward then back.
Distance
: Moving distance in one direction in revolution.
Start
/
Stop
: Start/Stop the motion.
Note
:
When you adjust the velocity by moving the slider forth and back, the motor velocity would not
change immediately as you expected. That is because the driver only read the new speed when it
changes direction. Also be careful about the initial direction and moving distance if the motor is
installed on a machine. It is recommended that set low speed and small distance if you are not sure
whether the direction and distance is correct or not.
Procedure for Achieving Optimum Performance
Step 1:
Start the motion test by clicking
Start/Stop
button. Find a resonance speed by slightly moving
the slider bar of internal pulse generator back and forth. You can also use the arrow keys to adjust the
speed precisely.
Step 2:
Run the motor at the resonance speed and verify the motor smoothness. You may find a better
smoothing value by slightly moving the slider bars of
AMP
(s) and
Phase
(s) back and forth.
It is very important to make the
AMP
(s) and
Phase
(s) adjustments at the proper test speeds with an
unloaded motor. Running at an incorrect test speed will not excite the motor at its peak resonance,
making it more difficult to find proper adjustment values. Optimum
AMP
(s) and
Phase
(s) values may
be a little different between running the tests with an unloaded motor and a load motor.
For example, we find a resonance speed at 0.98 rps. We begin to move the Amp1 slider forth and the
motor vibration and noise became lower and lower. Finally we find the move is the smoothest when
Amp 1
is 3300. The motor vibration and noise increase if
Amp 1
exceeds 3300. Then we follow the
same procedure to search the best point for
Phase 1
. See Figure 26. Anti-resonance tuning is done.
Please remember to click
Write EEprom
to write the final parameter settings to the driver when
finish tuning.
Web Site: www.helixlinear.com
Web Site:
www.helixlinear.com
