Siemens SINUMERIK 840D sl Programming Manual page 110

Fundamentals
2.7 Feed control
The setting made with FGROUP can be changed:
1. By reprogramming FGROUP: e.g. FGROUP(X,Y,Z)
2. By programming FGROUP without a specific axis: FGROUP()
In accordance with FGROUP(), the initial setting in the machine data applies: Geometry
axes are now once again traversed in the path axis grouping.
Note
With FGROUP, axis identifiers must be the names of channel axes.
Units of measurement for feedrate F
In addition to the geometrical settings G700 and G710, the G commands are also used to define
the measuring system for the feedrates F. In other words:
● For G700: [inch/min]
● For G710: [mm/min]
Note
G70/G71 have no effect on feedrate settings.
Unit of measurement for synchronized axes with limit speed FL
The unit set for F using G command G700/G710 is also valid for FL.
Unit for rotary and linear axes
For linear and rotary axes which are combined with FGROUP and traverse a path together, the
feedrate is interpreted in the unit of the linear axes (depending on the default with G94/G95, in
mm/min or inch/min and mm/rev or inch/rev).
The tangential velocity of the rotary axis in mm/min or inch/min is calculated according to the
following formula:
F[mm/min] = F'[degrees/min] * π * D[mm]/360[degrees]
where: F:
110
Tangential velocity
F': Angular velocity
π: Circle constant
D: Diameter
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
NC programming