HEIDENHAIN TNC 640 User Manual page 503

Special Functions | Global Program Settings (option 44)
Control display
Both the additive offset of the Global Program Settings function
and the offsets from Preset management affect the actual
position display.
The general status display shows the following icons:
For offsets from Preset management, no icon is
displayed!
Additive offsets active (default icon of the Global
Program Settings function)
The additive offset values are displayed on the GS tab of the
additional status display.
exclusively displayed in Preset management!
Application example
Increase traverse path:
Machine with AC fork head
Eccentric tool holder (outside the rotation center of the C axis)
presetToAlignAxis (no. 300203) machine parameter for the C
axis is set to FALSE
Traverse path is increased by means of a 180° rotation of the C
axis
Rotation is achieved by means of the Additive offset (M-CS)
option
Open the Global Program Settings function
Activate the Additive offset (M-CS) option with C = 180°
If necessary, add an L C+0 positioning movement to the NC
program
Reselect the NC program
The control considers the 180° rotation for all C axis positioning
movements.
The control takes the modified tool position into account.
The position of the C axis does not affect the preset position.
The preset remains unchanged!
HEIDENHAIN | TNC 640 | ISO Programming User's Manual | 10/2017
Offsets from Preset management are
12
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