Fluke 8021B - Battery;Backup Fuse Replacement; Cleaning

8021
B
2.
On the bottom
of the pcb
locate and
remove the two
Phillips screws
from the
display
assembly.
3.
Lift the
display assembly from
the pcb to
expose U
1.
CAUTION
U1 is a
MOS
device and
is subject to
damage by
static discharge.
Observe the
precautions given
later in this
section under
troubleshooting before
attempting
to remove
or replace U1.
4. Use a
screw driver ora
reasonable
substitute to rock (by
prying up
on each end
of
the
1C)
the 1C
out of it socket.
5.
When
installing
U
I
make sure all pins
are lined up
in the
socket, and
then
carefully
press it
into place.
4-17, Cleaning
CAUTION
Do not use
aromatic
hydrocarbons
or chlorinated
solvents
for cleaning.
These
solutions
will react with the
plastic
materials used
in the
instrument.
CAUTION
Do not
allow the
liquid crystal
display to get wet.
Remove
the Display
Assembly
before
washing the pcb
and do
not install it until
the pcb
has been
fully dried.
4-18.
Clean
the front
panel and case
with a mild
solution of
detergent
and water.
Clean
dust
from the
circuit
board with
low pressure
(20
psi) dry
air.
Contaminates
can be
removed
from the
circuit board
with
demineralized
water and a
soft brush
(remove the
Display
Assembly
before
washing, and
avoid getting
excessive
amounts of
water on the
switches).
Drywith clean,
dry air at
low pressure,
and then
bake at 50 to
60°C
(124-140°
F)
for
24 hours.
4-19. Battery/Backup
Fuse
Replacement
WARNING
BATTERY/FUSE
REPLACEMENT SHOULD
ONLY BE
PERFORMED
AFTER
THE
TEST LEADS
HAVE BEEN
REMOVED FROM
THE
INPUT JACKS
AND
THE POWER
SWITCH IS
SET TO
OFF. THE
BACKUP FUSE
REPLACEMENT
PROCEDURE
MUST BE
PERFORMED BY
QUALIFIED
SERVICE
PERSONNEL
ONLY. USE ONLY
THE
RECOMMENOED
FUSE
TYPE FOR
REPLACEMENT.
4-20. Refer to
Section 2 of this
manual for
battery and
main fuse
(FI)
replacement
procedure. Use the
following
procedure to replace
the backup
fuse (F2):
1 .
Complete the
Backup Fuse and
Calibration
Access
procedure located
earlier
in
this
section.
4-5