
5.FUNCTION DESCRIPTIONS FANUC AC SPINDLE MOTOR αi series B-65280EN/05
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5.1.4 I/O Signals (CNC ↔ PMC)
(1) Address list of input signals (PMC → CNC)
15i 16i 30i
#7 #6 #5 #4 #3 #2 #1 #0
1st- G227 G070 G070
CTH1A CTH2A
2nd- G235 G074 G074
CTH1B CTH2B
1st- G226 G071 G071
RCHA RSLA
2nd- G234 G075 G075
RCHB RSLB
1st- G229 G072 G072
RCHHGA
2nd- G237 G076 G076
RCHHGB
(2) Details of input signals (PMC → CNC)
(a) Speed range switching request signal (RSLA)
(1) The RSLA signal is used as a command signal for selecting an
output characteristic.
0: The high-speed characteristic is selected.
1: The low-speed characteristic is selected.
(2) Method of specifying the RSLA signal according to the speed
command (S command)
Input the RSLA signal in such a way that, if the specified speed
is lower than or equal to the switching speed, the low-speed
characteristic is selected and, if the specified speed is higher than
or equal to the switching speed, the high-speed characteristic is
selected. When this signal changes from 0 to 1 in a rotation speed
range that is higher than or equal to the switching speed, the
low-speed characteristic is selected immediately. To avoid this
symptom, set, to 1, a parameter (bit 4 of parameter No. 4019) for
selecting the low-speed characteristic after the speed detection
signal (SDTA) has changed to 1. This method requires that the
detection level of the SDTA signal be set to the switching speed.
(3) Method of using the speed-detected signal (SDTA)
Input the speed range switching request signal according to the
output of the SDTA signal. This method requires that the
detection level of the SDTA signal be set to the switching speed.
Note that the SDTA signal changes in the following cases:
• If the motor speed crosses the speed detection level during
constant surface speed control
When the motor is used with the low-speed characteristic,
clamping the maximum rotation speed of the spindle under
constant surface speed control to the switching speed (using
the G50 and G92 commands) prevents speed range
switching.
• If the motor speed crosses the speed detection level when
the speed is changed under spindle override