Siemens SINUMERIK 840D sl Programming Manual page 22

General
1.4 Reference points on the machine and workpiece
Reference points
The position of tool reference point F in the machine coordinate system is displayed with
machine zero M as the machine actual value.
The position of the tool tip (active tool) in the workpiece coordinate system is displayed with
workpiece zero W as the workpiece actual value. If a workpiece probe is active, the position
usually refers to the center point of the probe ball.
The zero offset (ZO) characterizes the position of the workpiece on the machine.
The ZO is the position of workpiece zero W in the machine coordinate system.
In addition to the pure offset, a ZO might also include rotation, mirroring, and a dimension
factor. Together these are termed a frame.
SINUMERIK controls use numerous frames: various basic frames, system frames, settable
frames (e.g. G54), programmable frames: They interact in a frame chain to produce the
overall frame and the workpiece coordinate system.
Measuring cycles do not support any frames with an active scale factor. Rotation or mirroring
is not supported in some cycles and measuring variants.
The machine and workpiece coordinate system can be set and programmed separately in
the "inch" or "metric" measuring system.
1-6
Z
Z1
W
Y1
M
X1
Programming Manual, Release 04/2006, 6FC5398-4BP10-0BA0
F
L1
Y
X
Measuring cycles