
B-63944EN/02 PROGRAMMING 7.COORDINATE SYSTEM
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If an absolute position detector is provided, the workpiece coordinate
system automatically set at power-up has its origin displaced from the
machine zero point by the G54 workpiece origin offset value. The
machine position at the time of power-up is read from the absolute
position detector and the current position in the workpiece coordinate
system is set by subtracting the G54 workpiece origin offset value
from this machine position. The workpiece coordinate system set by
these operations is shifted from the machine coordinate system using
the commands and operations listed below.
(a) Manual intervention performed when the manual absolute signal
is off
(b) Move command executed in the machine lock state
(c) Movement by handle interruption
(d) Operation using the mirror image function
(e) Shifting the workpiece coordinate system by setting the local
coordinate system or workpiece coordinate system
In the case of (a) above, the workpiece coordinate system is shifted by
the amount of movement during manual intervention.
WZn
-
Machine zero point
Workpiece origin
offset value
WZo
G54 workpiece
coordinate system before
manual intervention
G54 workpiece coordinate
system after manual
intervention
Po
Pn
mount of
movement during
manual intervention
In the operation above, a workpiece coordinate system once shifted
can be preset using G code (G92.1) specification or MDI operation to
a workpiece coordinate system displaced by a workpiece origin offset
value from the machine zero point.
Bit 3 (PPD) of parameter No. 3104 specifies whether to preset relative
coordinates (RELATIVE) as well as absolute coordinates.
When no workpiece coordinate system option (G54 to G59) is
selected, the workpiece coordinate system is preset to the coordinate
system with its origin placed at the reference position.