ADLINK Technology cPCI-8168, Руководство пользователя

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Operation Theory 69
4.3.4 Servo alarm signal
The alarm signal is an output signal from the motor driver. It tells
the motion controller that there is an error inside the servo motor
or driver. Once the motion controller receives this signal, the pulse
commands will stop sending and the ALM signal will be ON. The
reason for the alarm could be that the servo motor is over speed,
over current, over loaded and so on. Please check the motor
driver’s manual about the details.
The logic of an alarm signal must be set correctly. If the alarm
logic’s setting is not the same as the motor driver’s setting, the
ALM status will always be ON and the pulse command can never
be outputted.
4.3.5 Error clear signal
The ERC signal is an output from the motion controller. It tells the
motor driver to clear the error counter. The feedback position will
always have a delay from the command position. The error
counter counts and displays the difference between command
pulses and feedback pulses. Motor driver use the error counter as
a basic control index. The larger the error counter value, the faster
the motor speed command will be set. If the error counter is zero,
then zero motor speed command will be set.
In the following four situations, the ERC signal will be outputted
automatically from the motion controller to the motor driver in
order to clear the error counter at the same time.
1. Home return is complete
2. The end-limit switch is touched
3. An alarm signal is active
4. An emergency stop command is issued
4.3.6 Servo ON/OFF switch
The servo on/off switch is a general digital output signal on the
motion controller. It is defined as an SVON pin on the connector
and is used to switch to and from the motor driver’s controlled
state. When servo switch is on the motor will be held in place in
place as the control loop of driver is active. When the axis is verti-