
B-63943EN/02 9.STOP AND EMERGENCY STOP
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9.3 STOPPING THE SPINDLE MOTOR
While the spindle motor is running, shutting off the motor power
allows the spindle motor to coast at a speed maintained before shut-off
and eventually stop (after a while). However, there may be cases
where the spindle motor should be stopped as soon as possible for
safety reasons. In such cases, a stop of the spindle motor depends on
a Ladder program prepared by the machine tool builder. If the CNC
detects an abnormal condition, it outputs an alarm to the PMC. The
Ladder program should specify processing to be performed when an
alarm is output: allowing the spindle to continue running,
decelerating the spindle to a stop, or causing the spindle to coast, for
example.
To decelerate the spindle to a stop, a spindle emergency stop signal
(such as *ESPA (G71.1) or *ESPB (G75.1)) can be input in the PMC.
Inputting this signal cause the spindle to be decelerated to a stop. (A
Ladder program must be created so that this signal is input if an alarm
occurs.) The same effect can be achieved by using the PSM
emergency stop input (connector CX4). When an emergency stop
signal is connected to the *EMGPSM emergency stop input
(connector CX4), therefore, the spindle is decelerated to a stop if the
CNC enters the emergency stop state.
CAUTION
1 If the CNC enters the system alarm state, the
Ladder program does not run. In this case, the
spindle amplifier can be decelerated to a stop.
Make proper parameter settings because such a
stop depends on the settings.
2 If the spindle motor cannot be controlled due to an
alarm in the spindle amplifier itself or for some
other reason, the motor power is shut off by the
IGBT immediately. After the servo motor has
stopped, an MCC control signal is output.