
B–63173EN–1/01
9. SPINDLE SPEED FUNCTION
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D When gear selection output signals, GR2O and GR1O <F034 #0, #1>,
are used (in which constant surface speed control is not provided and
GTT, bit 4 of parameter No. 3706, is set to 0)
Set two gears, which are almost the same.
(Example: Value of parameter No. 3741 = value of parameter No.
3742 – 1, value of No. 3742 = Maximum spindle speed)
When parameter No. 3741 is equal to parameter No. 3742, the CNC
judges that one gear is used, and does not output the GR2O signal.
D The parameters related to gear switching points, SGT, bit 3 of
parameter No. 3705, and SGB, bit 2 of parameter No. 3761, parameter
Nos. 3761 and 3751 can be used.
D In usual spindle control, depending on the speed at switching points,
the speed specified by the spindle speed command may differ slightly
from the actual speed in the area where the maximum spindle speed
is set to the maximum speed 1. (This is because the spindle motor
speed, specified by the speed command, is calculated based on the
settings of parameter Nos. 3741 to 3744.)
This does not apply to rigid tapping. (Because the machine tool is
controlled using the feedback signal from the detector in the position
loop.)
D When gear selection input signals, GR1 and GR2 <G028 #1, #2>, are
used (in which constant surface speed control is provided or GTT, bit
4 of parameter No. 3706, is set to 1)
Parameter settings are read according to the input signal information.
Unlike the GR2O and GR1O signals, these signals do not require
special parameter settings.
Example) When parameter Nos. 3741 and 3742 are set to the maximum
spindle speed.
Create a PMC sequence that specifies the following.
For gear 1, set GR1 and GR2 to 0.
For gear 2, set GR2 to 0 and set GR1 to 1.
The PMC must determine the switching timing on the basis of some
information.
CONNECTION MANUAL
(This manual)
9.3
9.5
Spindle control
Rigid tapping
FANUC SERVO
AMPLIFIER series
DESCRIPTIONS
(B–65162E)
11.9 Output switching control
FANUC AC SPINDLE
MOTOR series
PARAMETER MANUAL
(B–65160E)
2.7 Output switching control
Reference item