NCT Group NCT 990T - Manual (Page 111)

13.4 Automatic Operation Restart with BLOCK RESTART Condition
111
5
th
case: Return to block start position after interrupting machining in offset mode at outside
corner
By the use of BLOCK RE-
START condition it
is set out from the offset
vector on the start position
of the interrupted block,
the length of which is mul-
tiplied by the length of the
new tool radius and
divided by the old one:
Afterwards the machining
is continued on the tool path with the new offset value.
When returning to start position of the block the control also returns all axes.
6
th
case: Return to block start position after interrupting machining in offset mode at inside
corner
When the BLOCK RE-
START condition is
on, machining inside a cor-
ner corresponds to that of
outside a corner. However
this time, as seen on the
diagram, if one of the
blocks is a circle, it cuts
into the workpiece. This
can be surmounted if the
tool is not returned fully to
the start position, but is
stopped earlier and
BLOCK RESTART
condition is switched off.
From than on it corre-
sponds to the process dis-
cussed in the chapter “Unconditional Restart of Automatic Mode”. Another possibility is to
start a block search for the interrupted block, however this is the province of another chapter.