Rockwell Automation 8520 9/Series CNC Lathe - Manual (Page 311)

Chapter 11
Coordinate System Offsets
11-5
Figure 11.3
Work Coordinate System
Zero point on
the part drawing
Workpiece
Chuck
Workpiece
Zero point on the work
coordinate system
Tool position at
machine coordinate zero point
Z Distance to be designated
X Distance to be designated
There are 7 preset work coordinate systems selected using G54 - G59.3.
The required work coordinate system can be selected by specifying any of
these G-codes in the program.
Work coordinate systems called out by G54 - G59.3 have zero points that
you enter in a work coordinate system table (see page 4.3). These zero
points are in the form of offset values from the machine coordinate system
zero point.
The control establishes the machine coordinate system immediately after
you complete the machine home operation The default work coordinate
system, determined in AMP by your system installer, is activated
simultaneously. The default work coordinate system is established when
you execute a control reset operation, E-STOP, G92.1, or power up. The
default work coordinate system is the sum of the external offset value (if
any), and the offsets of the default coordinate system selected in AMP
(G54-G59.3 or none). If the default coordinate system is selected as none,
the default work coordinate system is simply the external offset (if any).
This manual assumes G54 to be the default coordinate system and no
external offset has been entered.