HEIDENHAIN iTNC 530 (60642x-04) ISO programming - Manual (Page 556)

556 Test Run and Program Run
16.3
Test
Run
Danger of collision!
The TNC cannot graphically simulate all traverse motions
actually performed by the machine. These include
 Traverse motions during tool change, if the machine
manufacturer defined them in a tool-change macro or via
the PLC
 Positioning movements that the machine manufacturer
defined in an M-function macro
 Positioning movements that the machine manufacturer
performs via the PLC
 Positioning movements that lead to a pallet change
HEIDENHAIN therefore recommends proceeding with
caution for every new program, even when the program
test did not output any error message, and no visible
damage to the workpiece occurred.
After a tool call, the TNC always starts a program test at
the following position:
 In working plane in the center of the defined workpiece
blank
 In the tool axis, 1 mm above the MAX point defined in the
BLK FORM
If you call the same tool, the TNC resumes program
simulation from the position last programmed before the
tool call.
In order to ensure unambiguous behavior during program
run, after a tool change you should always move to a
position from which the TNC can position the tool for
machining without causing a collision.
Your machine tool builder can also define a tool-change
macro for the Test Run operating mode. This macro will
simulate the exact behavior of the machine. Please refer
to your machine tool manual.