
TITLE
FANUC Series 16i/18i/21i-TB
AI nano contour control
Specifications
EDIT. DATE DESIG. DESCRIPTION
FANUC LTD
SHEET
25/37
DRAW. NO.
A-78962EN (2) is added. 2003.03.27 02
CUST.
1784 Feedrate when overtravel alarm has occurred during acceleration / deceleration before
interpolation
Data type : Word
Unit of data : Increment system Unit of data Valid range
Valid range : IS-B IS-C IS-D
(2)
Millimeter machine 1 mm/min 6 to 15000 6 to 12000 6 to 10000
Inch machine 0.1 inch/min 6 to 6000 6 to 4800 6 to 4000
In this parameter, set the feedrate when an overtravel alarm occurs during the acceleration /
deceleration before interpolation.
When an overtravel alarm occurs during the acceleration / deceleration before interpolation, the tool is
overrun the amount of the deceleration distance because the deceleration stop is done after an
overtravel alarm occurs. The overrun distance changes depending on the feedrate at an overtravel
alarm. Therefore, the deceleration starts beforehand to reach the feedrate set in the parameter No.1784
when an overtravel alarm occurs (when a limit is reached) during the acceleration / deceleration before
interpolation. And the overrun distance that occurs at an overtravel alarm can be reduced. In this case,
to decelerate so that the feedrate set in parameter is greater than the feedrate at an overtravel, the
deceleration is occasionally completed early. The feedrate after the deceleration is completed becomes
the feedrate of the parameter setting value.
The deceleration is done at following conditions.
≤
Distance to stored
stroke limit for each
axis
Distance to decelerate from current feedrate
(feedrate in direction of tangent) to feedrate
of parameter setting
And the overrun distance is as follows.
Overrun distance ≤
FIX
Fot T
×
+
15
2
.
F 8
1875
×
F
T
F : Maximum machining speed during linear acceleration / deceleration before
interpolation. (Parameter No.1770)
T : Time constant during linear acceleration / deceleration before interpolation.
(Parameter No.1771)
Fot : Feedrate at overtravel alarm during linear acceleration / deceleration before
interpolation. (Parameter No.1784)
FIX : Round down below decimal point
(Note1) This parameter is ineffective for G00 block.
(Note2) When 0 is set in this parameter, the control described above is not executed.
(Note3) When the stored stroke limit check is ineffective, the control described above is ineffective.
(Note4) The control described above is applicable only to the stored stroke limit 1.