Siemens SINUMERIK 840DE Programming Manual page 277

Programming
FD=...
Or
FDA[axis]=0 or FDA[axis]=...
Or
FDA[axis]=...
Parameters
FD=...
FDA[axis]=0
FDA[axis]=...
Axis
The handwheel override function is non-modal. The function is deactivated in the next NC
block and the NC program continues to be executed.
Example
Path specification: The grinding wheel oscillating in the Z direction is moved to the workpiece
in the X direction using the handwheel.
The operator can then adjust the position of the tool until the spark generation is constant.
When "Delete distance-to-go" is activated, the program goes to the next NC block and
machining continues in NC mode.
Fundamentals
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
7.9 Feedrate with handwheel override (FD, FDA)
Handwheel travel for path axes with feedrate override
Handwheel travel for positioning axes according to
position parameter
Handwheel travel for positioning axes with feedrate
override
Positioning axes or geometry axes
Feedrate Control and Spindle Motion
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