
PROGRAMMING
B–63444EN/01
6. REFERENCE POSITION
63
NOTE
When parameter No. 1428 is set to 0, the feedrates conform
to the parameter settings shown below.
Before a coordinate
system is established
After a coordinate
system is established
Automatic reference posi-
tion return (G28)
No. 1420 No.1420
Automatic rapid traverse
(G00)
No.1420 No.1420
Manual reference position
return
No.1424 No.1424
Manual rapid traverse rate No.1423 *1 No.1424
1420 : Rapid traverse rate
1423 : Jog feedrate
1424 : Manual rapid traverse rate
*1 Setting of parameter No.1424 when RPD (bit 0 of parameter No.1401)
is set to 1.
The lamp for indicating the completion of return does not go on when the
machine lock is turned on, even when the tool has automatically returned
to the reference position. In this case, it is not checked whether the tool
has returned to the reference position even when a G27 command is
specified.
When the G28 command is specified when manual return to the reference
position has not been performed after the power has been turned on, the
movement from the intermediate point is the same as in manual return to
the reference position.
In this case, the tool moves in the direction for reference position return
specified in parameter ZMIx (bit 5 of No. 1006). Therefore the specified
intermediate position must be a position to which reference position
return is possible.
In an offset mode, the position to be reached by the tool with the G27
command is the position obtained by adding the offset value. Therefore,
if the position with the offset value added is not the reference position, the
lamp does not light up, but an alarm is displayed instead. Usually, cancel
offsets before G27 is commanded.
When the machine tool system is an inch system with metric input, the
reference position return lamp may also light up even if the programmed
position is shifted from the reference position by 1µ. This is because the
least input increment of the machine tool system is smaller than its least
command increment.
See III–3.1.
Restrictions
D Status the machine lock
being turned on
D First return to the
reference position after
the power has been
turned on
D Reference position
return check in an offset
mode
D Lighting the lamp when
the programmed position
does not coincide with
the reference position
Reference
D Manual reference
position return