JUKI MOL-254 Engineer's Manual page 233

No. Phenomenon
26 X/Y sewing table feed varies. X-axis feed steps out.
Y-axis feed steps out.
Feed completely fails to move.
Optional user's sewing data is used.
27 Power specifications have been Power voltage has been changed.
changed.
Number of power phases has been changed from 3-phase to
single phase.
Number of power phases has been changed from single-phase
to 3-phase.
Detailed state
Move the table by hand in the direction of X-axis and remove the mechanical
cause when the table does not move smoothly.
Check whether the cloth is pulled while the move of garment body to the next
loop sewing place during sewing is considered.
It is considered that connector CN109 or J62 is disconnected, or the cable has
broken. Correctly connect it.
Move the table by hand in the direction of Y-axis and remove the mechanical
cause when the table does not move smoothly.
It is considered that connector CN110 or J62 is disconnected, or the cable has
broken. Correctly connect it.
It is considered that connector CN7, CN109, CN110, J60, J61 or J62 is
disconnected, or the cable has broken. Correctly connect it.
It is considered that sewing cannot be performed at the max. spec. number of
rotations in accordance with the sewing data pattern (pattern of cloth feed as
against needle) created by the user. Consult us about this matter since it is
considered that setting of the max. number of rotations as against each pitch of
the user's data is necessary.
There is also a case where simply reducing the max. number of rotations with
the operation box panel is effective.
Change-over of the transformer input tap can meet whichever voltage, 220V,
230V, 240V, 380V or 480V. Perform the work referring to the item "Change-over
of the power specifications".
It is possible to change the 3-phase power specifications to the single-phase
power specifications by simple remodelling. Perform the work referring to the
item "Change-over of the power specifications".
In order to change the single-phase power specifications to the 3-phase power
specifications, it is necessary to perform the troublesome work of remodelling to
some extent. Perform the work of the cable by reversing the remodelling procedure
of 3-phase → single-phase referring to the item "Change-over of the power
specifications".
(Actually, all installation of electric equipment of this machine is of single-phase
and the power cable is not electrically connected even when the power cable is
changed to the 3-phase specifications. The machine operates normally even
when the single-phase power cables are connected to two cords in the 3-phase
power.
Checking point and corrective measure Replacing part
PMDC circuit board
X-axis stepping motor
Y-axis stepping motor
Power cable
(Remodelling accepted)
Power cable
(Remodelling accepted)