
B-65280EN/05 FANUC AC SPINDLE MOTOR αi series 3.I/O SIGNALS (CNC ↔ PMC)
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(b) Clutch/gear signals (CTH1A, CTH2A)
(1) When there are two or more gear change stages between the
spindle and spindle motor, these signals are used to select spindle
control parameters (position gain, gear ratio, and velocity loop
gain) for each gear. These signals are also used for a motor
having an speed range switching function to select control
parameters for each winding.
(2) Make settings as listed in the table below according to the state
of the clutch or gear. The names such as HIGH GEAR are given
for convenience, and the correspondence to the actual gears is
free.
CTH1A CTH2A
0 0 HIGH GEAR
0 1 MEDIUM HIGH GEAR
1 0 MEDIUM LOW GEAR
1 1 LOW GEAR
(c) Forward rotation command signal (SFRA) and reverse rotation command
signal (SRVA)
(1) When the following four conditions are satisfied, the spindle
motor starts forward or reverse rotation according to the speed
command (a positive value):
<1> Emergency stop signal *ESPA is set to 1.
<2> Machine ready signal MRDYA is set to 1.
<3> Forward rotation command signal SFRA or reverse rotation
command signal SRVA is 1.
<4> The contact signal between ESP and 24 V (CX4 of the
PSM) is ON (closed).
(2) While SFRA is 1, the spindle motor rotates counterclockwise as
viewed from the shaft side at a specified speed (a positive value).
While SRVA is 1, the spindle motor rotates clockwise as viewed
from the shaft side according to the speed command (a positive
value).
(3) When SFRA is set to 0 or when SRVA is set to 0, the spindle
motor is stopped by regenerative braking. After the spindle motor
is stopped, the power element excitation signal is turned off to
interrupt power supply to the spindle motor.
NOTE
If the forward rotation command signal (SFRA) and
reverse rotation command signal (SRVA) are
specified at the same time, the spindle status error
(error 14) occurs, and the spindle motor is stopped.
When SFR = 1 When SRV = 1