11. EMERGENCY STOP SIGNAL
The emergency stop signal is controlled as an input signal for the CNC
(X8.4) and as an input to the power supply module (PSM) that directly
shut off the motor driving power.
When an emergency stop is performed, brake control is performed not to
cause the servo motor to fall. To do this, the servo–motor driving power
must be shut off with the brake applied. In actual operation, the following
two controls are required:
1) Processing of emergency stop for the CNC (X8.4)
When an emergency stop is input to the CNC, the motor is decelerated,
then excitation is turned off. If the brake control function shown below
is enabled, servo excitation is turned off after a time preset in the timer
The axis that controls the brake prevents the motor from falling if the
brake control function is enabled, and a timer value is set. As the timer
value, set a time required until the brake is applied, which is about 100
ms to 200 ms.
#5 #4 #3 #2 #1 #0
[Data type] Bit axis
BRKC The brake control function is:
0 : Disabled.
1 : Enabled.
2083 Brake control timer
Increment system : msec
Setting range : 0 to 16000
2) Direct shut–off of the motor driving power
To shut off the motor driving power directly, an emergency stop signal is
input to the PSM, and the AC power supplied to the servo motor through
the PSM contact output is turned off. In this case, when brake control is
to be performed not to cause the servo motor to fall, the servo motor
driving power must be shut off with the brake applied.
Therefore, it is necessary to delay the emergency stop signal input to the
PSM for the timer value set in 1) above. For this reason, an off–delay
timer needs to be provided outside the PSM.
Brake control at
D Emergency stop signal
D Brake control