IBM IntelliStation 6836, Hardware Maintenance Manual

Page: 122 / 164

Electrical safety
CAUTION:
Electrical current from power, telephone, and communication cables can be
hazardous. To avoid personal injury or equipment damage, disconnect the
attached power cords, telecommunication systems, networks, and modems before
you open the computer covers, unless instructed otherwise in the installation
and configuration procedures.
Observe the following rules when working on electrical equipment.
Important: Use only approved tools and test equipment. Some hand tools have
handles covered with a soft material that does not insulate you when
working with live electrical currents.
Many customers have, near their equipment, rubber floor mats that
contain small conductive fibers to decrease electrostatic discharges. Do
not use this type of mat to protect yourself from electrical shock.
v
Find the room emergency power-off (EPO) switch, disconnecting switch, or
electrical outlet. If an electrical accident occurs, you can then operate the switch
or unplug the power cord quickly.
v
Do not work alone under hazardous conditions or near equipment that has
hazardous voltages.
v
Disconnect all power before:
– Performing a mechanical inspection
– Working near power supplies
– Removing or installing main units
v
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.
v
If you need to work on a machine that has exposed electrical circuits, observe
the 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.
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Hardware Maintenance Manual: IBM IntelliStation Type 6836, 6846