
6.1
6
l
REFERENCE POINT
Automatic
6.
REFERENCE POINT
Return to Reference Point (G28)
The reference point is a fixed position on a machine tool to which the tool can easily
be moved by the reference point return function.
Reference point
61
.
Automatic Return to Reference Point (G28)
G28P ;
This command specifies automatic return to the reference point. P
is’ an
intermediate coordinate and is commanded by absolute or incremental value.
The
intermediate coordinate specified in this block is stored in memory.
In the G28 block operation
0
Axis is positioned to intermediate coordinate. (A + B)
Q
Positioning is performed from intermediate coordinate to reference point. (B +
.
W
0
If the machine lock has not been set, the Reference Point Return lamp goes on.
Positioning to the intermediate point or to the reference point is done at rapid traverse
rate of each axis.
In general, this command is used ior automatic tool changing (ATC).
Reference
point
R
Fig.6.1
Operation of return to Refefrence point
(Note 1) When the G28 command is specified when manual return to the reference point has not been
performed after the power has been turned on, the movement is the same as in manual return to the reference
point. In this case, the direction is equal to that for return to reference point selected by parameter ZMX, Y
(No. 1006#5)
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