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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.
• 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.
• Do not work alone under hazardous conditions or near equipment that has
hazardous voltages.
• Disconnect all power before:
– Performing a mechanical inspection
– Working near power supplies
– Removing or installing Field Replaceable Units (FRUs)
• Before you start to work on the machine, unplug the power cord. If you cannot
unplug it, power off the wall box that supplies power to the machine and 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:
– 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 a tester, 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
