
4. REFERENCE POSITION ESTABLISHMENT
B–63503EN–1/01
150
Number Message Description
405 SERVO ALARM:
(WRONG ZRN)
Position control system fault. Due to
an CNC or servo system fault in the
reference position return, there is the
possibility that reference position re-
turn could not be executed correctly.
Try again from the manual reference
position return.
CAUTION
1 The tool is moved from the intermediate point in a sequence
similar to manual reference position return, if the G28
command is issued in the following cases:
· When the reference position has not yet been
established
· When the input increment (millimeter/inch) is changed at
a position other than the reference position
In these cases, the tool leaves the intermediate point in the
reference position return direction specified with bit 5 (ZMIx)
of parameter No. 1006. The intermediate point must
therefore be specified at a position from which reference
position return is possible.
2 If the G28 command is issued in the machine lock status,
the completion signal for reference position return is not set
to 1.
3 If millimeter input is selected for an inch–system machine,
the completion signal for reference position return may be
set to 1, even when the programmed tool position deviates
from the reference position by the least input increment.
This is because the least input increment is smaller than the
least command increment for the machine.
OPERATOR’S MANUAL
(For Machining Center)
(B–63514EN)
REFERENCE POSITION
OPERATOR’S MANUAL
(For Lathe) (B–63504EN)
REFERENCE POSITION
Alarm and message
Caution
Reference item