Galil DMC-1510, User Manual

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DMC-1500 Chapter 2 Getting Started
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the position reporting varies by one count only. If the encoder failed, replace the encoder. If you
cannot observe the encoder signals, try a different encoder.
3. There is a hardware failure in the controller- connect the same encoder to a different axis. If the
problem disappears, you probably have a hardware failure. Consult the factory for help.
Step 8a. Connect Standard Servo Motors
The following discussion applies to connecting the DMC-1500 controller to standard servo motor
amplifiers:
The motor and the amplifier may be configured in the torque or the velocity mode. In the torque
mode, the amplifier gain should be such that a 10 Volt signal generates the maximum required current.
In the velocity mode, a command signal of 10 Volts should run the motor at the maximum required
speed.
Step by step directions on servo system setup are also included on the WSDK (Windows Servo Design
Kit) software offered by Galil. See section on WSDK for more details.
Step A. Check the Polarity of the Feedback Loop
It is assumed that the motor and amplifier are connected together and that the encoder is
operating correctly (Step B)
. Before connecting the motor amplifiers to the controller,
read the following discussion on setting Error Limits and Torque Limits. Note that this
discussion only uses the X axis as an examples.
Step B. Set the Error Limit as a Safety Precaution
Usually, there is uncertainty about the correct polarity of the feedback. The wrong
polarity causes the motor to run away from the starting position. Using a terminal
program, such as DMCTERM, the following parameters can be given to avoid system
damage:
Input the commands:
ER 2000 <CR> Sets error limit on the X axis to be 2000 encoder counts
OE 1 <CR> Disables X axis amplifier when excess position error exists
If the motor runs away and creates a position error of 2000 counts, the motor amplifier
will be disabled.
Note: This function requires the AEN signal to be connected from the
controller to the amplifier.
Step C. Set Torque Limit as a Safety Precaution
To limit the maximum voltage signal to your amplifier, the DMC-1500 controller has a
torque limit command, TL. This command sets the maximum voltage output of the
controller and can be used to avoid excessive torque or speed when initially setting up a
servo system.
When operating an amplifier in torque mode, the voltage output of the controller will be
directly related to the torque output of the motor. The user is responsible for determining
this relationship using the documentation of the motor and amplifier. The torque limit
can be set to a value that will limit the motors output torque.
When operating an amplifier in velocity or voltage mode, the voltage output of the
controller will be directly related to the velocity of the motor. The user is responsible for
determining this relationship using the documentation of the motor and amplifier. The
torque limit can be set to a value that will limit the speed of the motor.
For example, the following command will limit the output of the controller to 1 volt on
the X axis: