HEIDENHAIN TNC 620 User Manual page 569

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
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.
With cuboid workpiece blanks, the TNC starts a
program test run after a tool call at the following
position:
In the working plane in the center of the defined
BLK FORM
In the tool axis, 1 mm above the MAX point
defined in the BLK FORM
With rotationally symmetric workpiece blanks, the
TNC starts a program test run after a tool call at the
following position:
In the machining plane at the position X=0, Y=0
In the tool axis 1 mm above the defined
workpiece blank
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. Refer to your machine manual.
HEIDENHAIN | TNC 620 | ISO Programming User's Manual | 9/2016
Test run 16.4
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