
B–64113EN–1/01
7. FEEDRATE CONTROL/ACCELERATION
AND DECELERATION CONTROL
438
1784 Speed when an overtravel alarm is issued during linear acceleration/deceleration
before interpolation
[Data type] Word
Valid data range
IS–A, IS–B IS–C
Millimeter machine 1 mm/min 6 to 15000 6 to 12000
Inch machine 0.01 inch/min 6 to 6000 6 to 4800
This parameter sets the speed to be reached when an overtravel alarm is
issued during linear acceleration/deceleration during interpolation. If an
overtravel alarm is issued during linear acceleration/deceleration before
interpolation, the movement is decelerated and halted after the issue of the
alarm. Therefore, the tool overruns by an amount equal to the distance
traveled during deceleration. The overrun varies depending on the
feedrate observed when the overtravel alarm is issued. The overrun can
be reduced by performing deceleration to the speed set in parameter 1784
in advance when an overtravel alarm is issued. In this case, deceleration
is performed so that the feedrate at the instant when the overtravel alarm
is issued does not exceed the parameter–set speed. So, deceleration may
be completed earlier. Upon the completion of deceleration, the feedrate
is set to the parameter–set speed.
NOTE
This parameter is invalid for rapid traverse blocks.
If the following condition is satisfied, deceleration is performed:
Distance to the
stored stroke limit
on an axis
Distance required for de-
celerating the current speed
(tangent direction feedrate)
to the speed set in parame-
ter 1784
<
The overrun is expressed as follows:
Overrun distance x
F
OT
F
T
8
FIX
1875
+ 1.5
2
F
T
F : Maximum machining feedrate during linear acceleration/deceleration
before interpolation (parameter 1770)
T :Time required to reach the maximum machining feedrate during linear
acceleration/deceleration before interpolation (parameter 1771)
F
OT
: Speed when an overtravel alarm is issued during linear
acceleration/deceleration before interpolation (parameter 1784)
FIX : Any fractional part is truncated.
[Unit of data]
[Valid data range]