Feedrate With Handwheel Override (Fd, Fda) - Siemens Sinumerik 840D sl Programming Manual

Feed control

8.8 Feedrate with handwheel override (FD, FDA)

Example:
Program code
...
N100 EVERY $A_IN[1] DO POS[X]=50 FA[X]=2000 ACC[X]=140
The current acceleration value can be called with system variable $AA_ACC[<axis>]. Machine
data can be used to define whether the last ACC value set should apply on RESET/part program
end or whether 100% should apply.
8.8 Feedrate with handwheel override (FD, FDA)
The FD and FDA commands can be used to traverse axes with handwheels during execution
of the part program. The programmed settings for traversing the axes are then overlaid with
the handwheel pulses evaluated as path or velocity defaults.
Path axes
In the case of path axes, the programmed path feedrate can be overlaid. The handwheel is
evaluated as the first geometry axis of the channel. The handwheel pulses evaluated per
interpolation cycle dependent on the direction of rotation correspond to the path velocity to be
overlaid. The path velocity limit values which can be achieved by means of handwheel override
are:
● Minimum: 0
● Maximum: Machine data limit values of the path axes involved in traversing
Note
Path feedrate
The path feedrate F and the handwheel feedrate FD cannot be programmed in the same
NC block.
Positioning axes
In the case of positioning axes, the travel path or velocity can be overlaid as an axial value.
The handwheel assigned to the axis is evaluated.
● Path override
The handwheel pulses evaluated dependent on the direction of rotation correspond to the
axis path to be traveled. Only handwheel pulses in the direction of the programmed position
are evaluated.
● Velocity override
The handwheel pulses evaluated per interpolation cycle dependent on the direction of
rotation correspond to the axial velocity to be overlaid. The path velocity limit values which
can be achieved by means of handwheel override are:
– Minimum: 0
– Maximum: Machine data limit values of the positioning axis
A detailed description of how to set handwheel parameters appears in:
References:
/FB2/ Function Manual, Extended Functions; Manual Travel and Handwheel Travel (H1)
120
Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
Fundamentals