Siemens SINUMERIK 828D Programming Manual page 144

Feed control
7.8 Feedrate with handwheel override (FD, FDA)
Further information
Traverse path axes with velocity override (FD=<velocity>)
The following conditions must be met for the part program block in which path velocity
override is programmed:
● Path command
● Exact stop
● Linear feedrate
Feedrate override
The feedrate override only affects the programmed path velocity and not the velocity
component generated with the handwheel (exception: (except if feed override = 0).
Example:
Program code
N10 X... Y... F500
N20 X... Y... FD=700
Traverse positioning axes with path default (FDA[<axis>]=0)
In the NC block with programmed
cannot generate any travel movement. The programmed travel movement to the target
position is now controlled exclusively by the operator rotating the handwheel.
144
, or
G1 G2
active
G60
active
G94
Description
; Feedrate = 500 mm/min
; Feedrate = 700 mm/min and velocity override
; with handwheel.
; Acceleration from 500 to 700 mm/min in N20. The handwheel
; can be used to vary the speed dependent on the direction of rotation between
; 0 and the maximum value (machine data).
active
G3
the feed is set to zero so that the program
FDA[<axis>]=0
Programming Manual, 07/2010, 6FC5398-1BP40-0BA0
Fundamentals