Cleaning; Battery/Backup Fuse Replacement - Fluke 8021B Instruction Manual

8021
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