IBM A40I TYPE 2271 Hardware Maintenance Manual page 132

Observe the following rules when working on electrical equipment.
v Find the room emergency power-off (EPO) switch, disconnecting switch, or
v Do not work alone under hazardous conditions or near equipment that has
v Disconnect all power before:
v Before you start to work on the machine, unplug the power cord. If you cannot
v If you need to work on a machine that has exposed electrical circuits, observe the
v Regularly inspect and maintain your electrical hand tools for safe operational
v Do not use worn or broken tools and testers.
v Never assume that power has been disconnected from a circuit. First, check that it
v Always look carefully for possible hazards in your work area. Examples of these
v Do not touch live electrical circuits with the reflective surface of a plastic dental
v Do not service the following parts (or similar units) with the power on when they
v If an electrical accident occurs:
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Hardware Maintenance Manual A40 Type 6840 A40P Type 6841 A40i Type 2271: IBM NetVista Computer
electrical outlet. If an electrical accident occurs, you can then operate the switch
or unplug the power cord quickly.
hazardous voltages.
– Performing a mechanical inspection
– Working near power supplies
– Removing or installing main units
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.
following precautions:
– Ensure that another person, familiar with the power-off controls, is near you.
Remember:Another person must be there to switch off the power, if
necessary.
– Use only one hand when working with powered-on electrical equipment;
keep the other hand in your pocket or behind your back.
Remember: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.
– When using testers, set the controls correctly and use the approved probe
leads and accessories 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.
condition.
has been powered-off.
hazards are moist floors, nongrounded power extension cables, power surges,
and missing safety grounds.
mirror. The surface is conductive; such touching can cause personal injury and
machine damage.
are removed from their normal operating places in a machine. This practice
ensures correct grounding of the units.)
– Power supply units
– Pumps
– Blowers and fans
– Motor generators
– Use caution; do not become a victim yourself.
– Switch off power.
– Send another person to get medical aid.