NCT Group NCT 990T - Manual (Page 106)

13.3 Unconditional Restart of Automatic Operation
106
The cases below refer to the axes in the selected plane in when offset mode is on. To interrup-
tion of axis movements outside the selected plane refer to interruption cases in state G40.
6 th case: in state G41 or G42 interrupting linear interpolation parallel to axis
Let us examine fragments of the following sample programs:
Program No. 1:
G41 G18 G90 G1...
...
N80 X40
N90 Z-30
...
Program No. 2:
G41 G18 G91 G1...
...
N80 X45
N90 Z-20
...
Both programs are on the same tool path,
however the data specification of the former
one is absolute, while that of the latter one is
incremental. If the machining is interrupted
in position X=20, Z=–10 the automatic
mode is closed and manual operation is used,
than after returning to automatic mode the
START button is pressed both axes taking
part in the contour tracking move to the pro-
grammed end position as seen on the dia-
gram, independently of the tool path having
programmed by the use of absolute data
specification or incremental data specifica-
tion. If in the above example yet another axis is moved by means of manual operation, after
pressing the START, no movement occurs on that axis, as discussed in the 1
st
case. If in single
block mode the automatic execution is interrupted in STOP state at the beginning of block
N80, after return and START, the tool path is recalculated as discussed above. If in the
meanwhile the value of the tool radius has been changed, it carries on cutting by taking the
new offset value into account.
7
th
case: in state G41 or G42 interrupting oblique linear interpolation
If during contour tracking the automatic operation is interrupted in the course of oblique linear
interpolation after return and START, the tool path is recalculated as discussed in the 6
th case.
8 th case: in state G41 or G42 interrupting circular interpolation
If in offset mode the automatic operation is
closed in the course of circular interpolation
after return to automatic mode and pressing
the START button the tool approaches the
end position programmed in the block along
a circle with a variable radius. The center of
the circle corresponds to the center of the
programmed one. Its starting radius equals
to the distance between the center of the
circle and the momentary tool position. The
end point radius of the circle corresponds to
the programmed one.