8. COORDINATE SYSTEM
A coordinate system used for machining a workpiece is referred to as a
workpiece coordinate system. A workpiece coordinate system is to be set
with the CNC beforehand (setting a workpiece coordinate system).
A machining program sets a workpiece coordinate system (selecting a
workpiece coordinate system).
A set workpiece coordinate system can be changed by shifting its origin
(changing a workpiece coordinate system).
A workpiece coordinate system can be set using one of three methods:
(1) Method using G92
A workpiece coordinate system is set by specifying a value after G92
in the program.
(2) Automatic setting
If bit 0 of parameter SPR No. 1201 is set beforehand, a workpiece
coordinate system is automatically set when manual reference
position return is performed (see Part III–3.1.).
(3) Input using the CRT/MDI panel
Six workpiece coordinate systems can be set beforehand using the
CRT/MDI panel (see Part III–11.4.6.).
When using an absolute command, establish the workpiece
coordinate system in any of the above ways.
(G90) G92 IP_
A workpiece coordinate system is set so that a point on the tool, such as
the tool tip, is at specified coordinates. If a coordinate system is set using
G92 during tool length offset, a coordinate system in which the position
before offset matches the position specified in G92 is set.
Cutter compensation is cancelled temporarily with G92.
If an absolute command is is-
sued, the base point moves to
the commanded position. In
order to move the tool tip to the
commanded position, the dif-
ference from the tool tip to the
base point is compensated by
tool length offset.
Setting the coordinate system by the
(The tool tip is the start point for the program.)
Setting the coordinate system by the G92X600.0Z1200.0; command
(The base point on the tool holder is the start point for the program.)
Setting a Workpiece
D Setting a workpiece
coordinate system by G92