Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set - Manual (Page 318)

Coordinate System Offsets
Chapter 11
11-2
Figure 11.1
Machine Coordinate System, Home Coordinate Assignment
Mechanically fixed
Machine Home
point
15
+X
+Y
Machine Coordinate System
zero point
10
In Figure 11.1 the system installer has defined the zero point of the
machine coordinate system by assigning the machine home point to have
the coordinates Y=10 and X=15 in the machine coordinate system.
Note that the coordinate values assigned to the machine home point do not
affect the position of machine home. The position of machine home is
fixed by the system installer.
Important: Normally the control displays the current position of the axis
in respect to an active work coordinate system. The position in the
machine coordinate system may be displayed by selecting the Absolute
screen as discussed in Chapter 8.
Although axis motion is usually commanded in the work coordinate
system, axis motion by referencing coordinate values in the machine
coordinate system is possible when a G53 is programmed in a block.
G90G53X__Y__Z__ ;
The X, Y and Z words above specify coordinate positions in the machine
coordinate system. These coordinate values indicate the end point of the
next move in the machine coordinate system. The tool travels to this
position in either G00 or G01 mode depending on which is active when the
G53 block is executed. Any attempt to execute a G53 block in G02 or G03
mode will generate an error.
The G53 code is not modal and is effective only in the block in which it is
called. After a G53 block the control returns to the positioning mode that
was in effect prior to the G53 block’s execution.
11.1.1
Motion in the Machine
Coordinate System (G53)