NCT Group NCT 990T - Manual (Page 104)

13.3 Unconditional Restart of Automatic Operation
104
2
nd
case: in state G40 interrupting oblique linear interpolation
Let us examine fragments of the following sample programs:
Program No. 1:
...
N40 G90 G0 X20 Z–10
N50 X80 Z–60
N60 Z–85
...
Program No. 2:
...
N40 G90 G0 X20 Z–10
N50 G91 X60 Z–50
N60 Z–25
...
Programs No. 1 and 2 are on the same
tool path, however the data specifica-
tion of the former one is absolute,
while that of the latter one is
incremental. The interruption occurs in
block N50. In position X=44, Z=–30
the movement is stopped, the
automatic mode is interrupted and the
axes are carried to position X=110,
Z=–30 by means of manual operation.
If afterwards the automatic mode is re-
turned, and the START button is
pressed the movement programmed in block N50 is finished. Axes X and Z move along
oblique straight from their momentary state to the position X=80, Z=–60 programmed, no
matter if the tool path has been written by the use of absolute data specification (program No.
1) or incremental data specification (program No.2).
The movement is the same, if in single block mode the automatic mode is closed in the start
position of block N50, manual operation is used, than after return the START button is
pressed.
Interrupting Canned Cycles
Let us examine the following cycle:
...
G17 G90 G81 X100 Y70 Z–60 R2 F200
...
In the view of interruption the canned cycle consists of 3 part blocks:
1
st
part block: Positioning in the selected plane. This block is referred to by control in the view
of interruption where only one or two coordinates (in the example X and Y)
have been programmed: G0 X100 Y70
2
nd
part block: Positioning on point R. This part block is in the view of interruption a
positioning along an axis. In the example it is the axis Z moving to the
value specified at address R: G0 Z2
3
rd
part block: Hole machining and retraction to initial position (G98) or to R-point (G99). In
this case the end position of the part block is the initial position or R-point.
At the end of all three part blocks the control stops in single block mode.
3
rd
case: Interrupting canned cycle in the course of positioning in the selected plane
If the movement is interrupted while moving to position X=100, Y=70 in the sample block,
than manual operation is used, after returning to automatic mode and pressing START button
movement is made as in the 2
nd
case, i.e., axes move to position X100 Y70.