IBM 6643 Personal Computer User Manual


 
3.
Check
the
power
cord
for
the
following:
a.
A
third-wire
ground
connector
in
good
condition.
Use
a
meter
to
measure
third-wire
ground
continuity
for
0.1
ohm
or
less
between
the
external
ground
pin
and
frame
ground.
b.
The
power
cord
should
be
the
appropriate
type
as
specified
in
the
parts
listings.
c.
Insulation
must
not
be
frayed
or
worn.
4.
Remove
the
cover.
5.
Check
for
any
obvious
non-IBM
alterations.
Use
good
judgment
as
to
the
safety
of
any
non-IBM
alterations.
6.
Check
inside
the
unit
for
any
obvious
unsafe
conditions,
such
as
metal
filings,
contamination,
water
or
other
liquids,
or
signs
of
fire
or
smoke
damage.
7.
Check
for
worn,
frayed,
or
pinched
cables.
8.
Check
that
the
power-supply
cover
fasteners
(screws
or
rivets)
have
not
been
removed
or
tampered
with.
Chapter
8.
Related
service
information
105