
B–64113EN–1/01
9. SPINDLE SPEED FUNCTION
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Although the S command contains the spindle speed, the object that is
actually controlled is the spindle motor. Therefore, the CNC must have
some provision to detect the gear stage between the speed and spindle
motor.
There are two types of gear selection methods:
M type
The CNC selects a gear stage according to the range of speed for each gear
stage previously specified in a parameter, as directed by the S command,
and informs the PMC of the selected gear stage (one of the three gear
stages ) using the gear select signal output (GR3O, GR2O, GR1O).
Also, the CNC outputs the spindle speed based on the selected gear stage
(output as the gear select signal).
T type
The gear stage (one of the four gear stages ) being currently used by the
machine is specified by the gear select signal inputs (GR1, GR2).
The machine determines which gear to use.
The CNC outputs the appropriate speed command for the selected gear
range.
The M series system can use either M or T type.
M type ← Without constant surface speed control option, and bit 4
(GTT) of parameter No. 3706 = 0
T type ← With constant surface speed control, or bit 4 (GTT) of
parameter No. 3706 = 1
The T series system can use only T type.
By specifying from S0 to S99999 in memory or MDI operation, the CNC
outputs a command corresponding to the spindle speed. There is a
two-speed (GR1O and GR2O) or three-speed range (GR1O, GR2O,
GR3O), set by parameter nos. 3741-3743, and the gear selection signal
is output simultaneously. When the gear selection signal is changed, the
SF signal is output at the same time (parameter SFA no. 3705#6).
The meaning of the gear signals is shown below:
Gear 2–stage Gear 3–state Remarks
GR1O Low Low
GR2O High Middle
Middle: Middle Gea
GR3O High
High: High Gear
D Processing for gear
changing
D Selection of gear change
system
D Details of M type
(Output of GR1O, GR2O,
GR3O)