
10. INTERFACE SIGNALS
B–65162E/03
372
D Because the spindle motor enters the power OFF, coasting operates at
the same time as the alarm signal is output, it is necessary to set in an
emergency stop state and to set the feedhold state at the CNC or
magnetics cabinet side.
D When the alarm state has occurred, ALMA = 1 occurs.
While the alarm signal is 1, the spindle motor enters coasting operates
state regardless of any command from the outside.
D The relationship between the alarm signal and the alarm reset signal
is as shown in Fig. 10.2.9.
Forward rotation/back
rotation command
SFRA (SRVA)
1
1
0
(Stop)
Motor rotation speed
Does not operate even
when there is a command
Usable state
Motor operation
Spindle control
output signal
Spindle control
input signal
0
Remove the alarm cause
(Alarm reset)
Speed command
ARSTA
(Alarm)
ALMA
0
Spindle orientatin
commandORCMA
Fig.10.2.9 Timing Chart of the Spindle Alarm Signal
D If the actual rotation speed of the spindle motor is reduced to be lower
than the zero-speed detection point for the stop command, SSTA = 1
occurs.
Zero-speed detection point
("0.75%of maximum speed
as the standard)
(0)
0
SSTA (1)
(1)
Motor
speed
Fig.10.2.10 Signal Indicating that the spindlespeed dropped
to close to zero
10.2.10
Zero-speed Detecting
Signal (SSTA)