Aerotech UNIDEX 600 Series, Руководство пользователя

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AerTune U600 User’s Guide
5-36
Aerotech, Inc.
Version 1.4
If the user is fine tuning the servo loop gains that Aerotech has setup for the system,
use the existing PGain as the starting point.
As PGain increases, the position error will begin to be at zero or near the end of the
commanded move. The axis is now roughly tuned, so continue with the following step.
7. This step requires fine tuning the amplifier settings. First, adjust the Balance pot
on the amplifier in order to remove any DC offset in the position error. Press the
Auto button to cycle the axis. While the axis is moving, adjust the Balance pot
and remove any DC offset in the position error. Press the Halt button when the
task is done. Ideally the position error will be symmetrical in the positive and the
negative directions. However, it is most important that the position error is at
zero when the move is complete.
Second, the user will fine tune the Current Limit pot on the Aerotech DS16020/16030
amplifier after commanding the motor to move short, fast moves and observing the
current feedback from TP1 on the amplifier with an oscilloscope. In order to do this,
perform the following steps.
a. Connect the Oscilloscope leads to TP1 (current feedback) and TP4
(common) on the amplifier.
b. Set the Distance and Speed entry fields to represent a typical short fast
move. The idea here is to command the motor to move faster than it is
capable, so that the amplifier will saturate. This implies that the amplifier is
full on, that is, commanding maximum current. This allows the user to
adjust the current limit potentiometer that limits the maximum current that
the amplifier can produce.
c. Press the Auto button and allow the axis to cycle.
If the user cycles the axis too long at short fast speeds, the fuse will blow, so be
prepared to make the adjustment fairly quickly. The user may desire to use the Step
buttons so there is a delay between moves preventing the fuse from blowing quickly.
d. While the axis is moving, adjust the Current Limit pot to limit the current to
either 4 times the continuous current rating of the motor or the peak current
rating of the motor, whichever is less.
The current feedback on TP1 is 3 amps per volt, so a 2 volt signal on the Oscilloscope
would represent 6 amps. Press the Halt button when complete. Figure 5-24 illustrates
what is seen after one move.