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Working near power supplies
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Removing or installing main units
Before you start to work on the machine, unplug the
power cord. If you cannot unplug it, ask the customer
to power-off the wall box that supplies power to the
machine and to lock the wall box in the off position.
If you need to work on a machine that has exposed
electrical circuits, observe the following precautions:
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Ensure that another person, familiar with the
power-off controls, is near you.
Attention: Another person must be there to
switch off the power, if necessary.
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Use only one hand when working with
powered-on electrical equipment; keep the other
hand in your pocket or behind your back.
Attention: There must be a complete circuit to
cause electrical shock. By observing the above
rule, you may prevent a current from passing
through your body.
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When using testers, set the controls correctly
and use the approved probe leads and accesso-
ries for that tester.
–
Stand on suitable rubber mats (obtained locally,
if necessary) to insulate you from grounds such
as metal floor strips and machine frames.
Observe the special safety precautions when you
work with very high voltages; these instructions are in
the safety sections of maintenance information. Use
extreme care when measuring high voltages. Regu-
larly inspect and maintain your electrical hand tools
for safe operational condition.
Do not use worn or broken tools and testers.
Never assume that power has been disconnected
from a circuit. First, check that it has been
powered-off.
Always look carefully for possible hazards in your
work area. Examples of these hazards are moist
floors, nongrounded power extension cables, power
surges, and missing safety grounds.
Do not touch live electrical circuits with the reflective
surface of a plastic dental mirror. The surface is
conductive; such touching can cause personal injury
and machine damage.
Do not service the following parts with the power on
when they are removed from their normal operating
places in a machine:
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Power supply units
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Pumps
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Blowers and fans
ThinkPad i Series 1400/1500
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