© Copyright IBM Corp. 1998 xiii
Electrical Safety
Observe the following rules wh en wor king on electrical
equipment.
Important
Use only approved tools and test equ ip ment. Some hand
tools have handles covered with a soft m at erial that does
not insulate you when working with live electrical currents.
Many customers have, near their equ ip m ent, rubber floor
mats that contain small c onductive fibers to d ecrease
electrostatic discharges. Do not use this type of mat to
protect yourself from electr ic al shock.
• Find the room emergency power-off (EPO) switch,
disconnecting switch, or elect r ic al outlet. If an
electrical accident occurs, you c an th en op erate 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 bef ore:
- Performing a mechanical insp ect i on
- Working near power supplies
- 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 wal l box that supplies power to the
machine and to lock the wall box in the off posit ion.
• If you need to work on a machine that has

exposed

electrical circuits, obs erve the following prec autions:
- 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.
- Use only one hand when wor k in g w ith
powered-on electrical equipment; keep the
other hand in your pocket or behind your bac k.
Attention: There must be a compl ete cir c uit
to cause electrical sh ock. By observing th e
above rule, you may pr event a current from
passing through your body.
- When using t esters, set the controls c orrectly
and use the approved pr obe leads and
accessories for that tester.
- Stand on suit able rubber mats (obtained
locally, if necessary) to insulate you from
grounds such as metal floor strips and
machine frames.
Observe the special safety prec aut ions when you
work with very high voltages; thes e ins tructions are in
the safety sections of mainten anc e information. Use
extreme care when measuring hig h voltages.