Galil DMC-4040, Руководство пользователя

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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. For Galil amplifiers, see Integrated .
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 correct
(Step 7)
. 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 A 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 Galil Tools, the
following parameters can be given to avoid system damage:
Input the commands:
ER 2000 <return>
Sets error limit on the A axis to be 2000 encoder counts
OE 1 <return> Disables A 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 AMPEN 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-40x0 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:
TL 1 <return>
NOTE: Once the correct polarity of the feedback loop has been determined, the torque limit should, in general,
be increased to the default value of 9.99. The servo will not operate properly if the torque limit is below
the normal operating range. See description of TL in the command reference.
Step D. Connect the Motor
Once the parameters have been set, connect the analog motor command signal (MCM n where n is A-H) to
the amplifier input.
To test the polarity of the feedback, command a move with the instruction:
PR 1000 <CR>
Position relative 1000 counts
BGA <CR>
Begin motion on A axis
When the polarity of the feedback is wrong, the motor will attempt to run away. The controller should
disable the motor when the position error exceeds 2000 counts. If the motor runs away, the polarity of the
loop must be inverted.
DMC-40x0 User Manual Chapter 2 Getting Started
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