Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set - Manual (Page 329)

Coordinate System Offsets
Chapter 11
11-13
This section discusses the more temporary ways of offsetting the work
coordinate systems. These offsets are activated through programming and
are cancelled when an M02 or M30 is executed, a control reset is
performed, or power to the control is turned off.
Important: All of these offsets are global in nature. This means that they
will apply to all of the work coordinate systems. When changing work
coordinate systems (Programming G54-G59.3), consideration should be
given to the effects of these offsets on the new work coordinate system.
Tool geometry and wear offsets are not affected by an offset to the work
coordinate system.
Important: It is recommended that tool offsets for geometry and wear be
cancelled before any work coordinate system offsets are executed. If tool
offsets are not cancelled, the work coordinate system offset will be added
to the active tool offset. This can cause confusion when changing tool
offsets later in the program (see chapter 20 on cancelling tool offsets).
The G92 command in a part program is used to offset the currently active
work coordinate system relative to the current tool position. A G92 block
in a program will offset the zero point of the work coordinate system a
specified distance from the current tool position.
When a G92 command is executed in a program it cancels any other active
work coordinate system offsets that may have been in effect including G52
offsets, jogged offsets, or set zero offsets. Note that external offsets are not
affected. When the PAL flag $INHR is set, it cancels G92.
Important: A tool offset is not automatically canceled when a G92 block
is executed. Be aware that this may result in undesired effects on the work
coordinate system when tool offsets are changed later.
The following G92 block offsets the work coordinate system so that the
current tool position takes on the coordinate values programmed in the
G92 block.
G92 X__ Y__ Z__;
For example specifying values of zero for all axes in a G92 block causes
the current tool position to become the zero point of the current work
coordinate system.
Execution of a G92 block does not produce any axis motion.
Important: Any axis not specified in the G92 block will not be offset, and
the current coordinate position for that axis will remain unchanged.
11.4
Offsetting the Work
Coordinate Systems
11.4.1
Coordinate Offset Using
Tool Position (G92)