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12 CONTROL AUXILIARY FUNCTIONS
12.5.2 Override function
The override function changes the command speed by a designated percentage (1 to
300%) for all control to be executed.
The speed can be changed by setting the percentage (%) by which the speed is
changed in "Positioning operation speed override (RWwm+1, RWwm+9)".
For a machine zero point return, however, override cannot be performed after start of
deceleration to the creep speed following the detection of Near-point dog ON.
(1) Control details
(2) Precautions during control
(3) Setting the override function
(1) Control details
The following shows that operation of the override function.
1) A value changed by the override function is monitored by "Feedrate
(RWrn+2 to 3, RWrn+10 to 11)".
2) If "Positioning operation speed override (RWwm+1, RWwm+9)" is set to
100%, the speed will not change.
3) If "Positioning operation speed override (RWwm+1, RWwm+9)" is set a
value less than 100%, control will be carried out at speed unit "1" at the time
"Feedrate (RWrn+2 to 3, RWrn+10 to 11)" becomes a value of "1" or less.
4) If there is not enough remaining distance to change the speed when the
speed is changed during the position control of speed/position changeover
control, the operation will be carried out at the speed that could be changed.
5) If the speed changed by the "override function" is greater than the "
Pr.7
Speed limit value", a warning "speed limit value over" (warning code: 501)
will occur and the speed will be controlled at the "
Pr.7 Speed limit value".
The "Speed limitting flag (RX(n+1)0, RX(n+4)0)" will turn ON.
Feedrate
Da. 7 Command speed
100
1
50 150
100
200
50
50 1 25
75
50 75
Not affected by the override value
during deceleration
Not enough remaining
distance could be secured,
so operation is carried out
at an increased speed.
t
V
Positioning operation
speed override
[RWrn+2 to 3,
RWrn+10 to 11]
[RWwm+1, RWwm+9]
Fig. 12.27 Override function operation