5238-E P-(iii)
SAFETY PRECAUTIONS
5.
Precautions during Maintenance Inspection and When
Trouble Occurs
In order to prevent unforeseen accidents, damage to the machine, etc., it is essential to observe the
following points when performing maitenance inspections or during checking when trouble has
occurred.
(1) When trouble occurs, press the emergency stop button on the operation panel to stop the
machine.
(2) Consult the person responsible for maintenance to determine what corrective measures need
to be taken.
(3) If two or more persons must work together, establish signals so that they can communicate to
confirm safety before proceeding to each new step.
(4) Use only the specified replacement parts and fuses.
(5) Always turn the power off before starting inspection or changing parts.
(6) When parts are removed during inspection or repair work, always replace them as they were
and secure them properly with their screws, etc.
(7) When carrying out inspections in which measuring instruments are used - for example voltage
checks - make sure the instrument is properly calibrated.
(8) Do not keep combustible materials or metals inside the control enclosure or terminal box.
(9) Check that cables and wires are free of damage: damaged cables and wires will cause current
leakage and electric shocks.
(10) Maintenance inside the Control Enclosure
a.
Switch the main power disconnect switch OFF before opening the control enclosure door.
b.
Even when the main power disconnect switch is OFF, there may some residual charge in
the MCS drive unit (servo/spindle), and for this reason only service personnel are permitted
to perform any work on this unit. Even then, they must observe the following precautions.
•
MCS drive unit (servo/spindle)
The residual voltage discharges two minutes after the main switch is turned OFF.
c.
The control enclosure contains the NC unit, and the NC unit has a printed circuit board
whose memory stores the machining programs, parameters, etc. In order to ensure that the
contents of this memory will be retained even when the power is switched off, the memory
is supplied with power by a battery. Depending on how the printed circuit boards are
handled, the contents of the memory may be destroyed and for this reason only service
personnel should handle these boards.
