Fluke 732a - Fuse Replacement; AC Line Voltage Change

732A
4. Do
the
same for
the
foam
block that is now
exposed.
5.
Locate
the
two mylar tabs
located on
each
side
of
the
Oven
Assembly.
6.
Grasp
both
mylar tabs and
pull steadily and
evenly
upwards.
7.
Disconnect
the
Oven
Assembly
cable
harness at
the
motherboard
and at
the
front
panel.
4-19. Oven
Disaseembly
4-20.
Use
the
following
procedure
to disassemble
the
Oven
Assembly.
Use
this
procedure
only
if
access
is
necessary
to
effect
repairs
on the
Oven Controller
circuit.
Do
not
attempt
to
repair
the
Reference
circuit.
1.
Remove
the
Oven
Assembly
from
the 732A.
2.
Lay
the
instrument
on
its
side,
with its top
facing
you,
and lay
the
Oven
Assembly
on
the
work
surface.
3.
Remove
the
four
screws
holding
the
inside
clamshell
(the
inside clamshell
contains
the
adjustment
holes
for
the
calibration
potentiometers)
NOTE
Do
not
turn
the
screws
on the
outside
clamshell
as
this
will cause
difficult
disassembly
and
reassembly.
4.
Move
the
wire
bundle to
the side
and
lift
the
heater
assembly
free
of the
Oven
Assembly.
5.
Lay
the
heater
assembly
to the
side.
The
Reference
PCB
Assembly
circuitry
is
now
accessible.
NOTE
In
most
cases,
repairs
to
the
PCB
assembly
can
be
better
accomplished from
the
component
side
of
the PCB.
If
access
to the
bottom
of
the
PCB
is
necessary,
unscrew
the
outside
four
teflon
standoffs.
4-21.
Front
Panel
Removal
4-22.
Use
the
following
procedure
to
detach
the
front
panel
from
the
732A:
1.
Remove
the
top
and
bottom
covers.
2.
With
the
732A
resting
on
its
bottom,
remove
the
screws
securing
the
inner
shield
cover
and
remove
the
cover.
3.
Locate
the Blue
wire coming
from the
GUARD
terminal
to
a solder
lug
riveted to
the chassis.
Unsolder
this
wire
at the solder
lug
and pull
it free.
4.
Peel
the
decal
from both of
the
front
corner side
moldings and
remove
the
exposed screws.
Refer
to
Figure
4-1
for screw
locations.
5.
Remove
the
front
corner side moldings from
the
instrument.
6. The
front
panel
is now
free.
Be
extremely
careful of
the
wire
harness connected to
the front
panel
binding
posts.
The
service loop
provided
is
quite
limited.
4-23.
Cleaning
CAUTION
To
prevent
possible
damage
to the front
panel,
do
not use
aromatic
hydrocarbons
or
chlorinated
solvents
on
the
front panel of
the
732A.
4-24. When
the
732
A is
properly cared
for and
kept in a
controlled
atmosphere,
cleaning is
seldom
required.
However,
any
contamination,
particularly oil,
in the
instrument
can
contribute
to
an
increase
in
leakage
which
may
impair
accuracy.
4-25. Clean
the
exterior
and
the front panel
of
the
732A
with a
soft
cloth
dampened
in
a
mild
solution
of
detergent
and
water.
Do
not
attempt
to
clean
the
interior
of
the
instrument.
4-26.
Fuse
Replacement
4-27. The
power fuse
FI is
located
on the
rear
panel
of
the
732A.
If
replacement
is
necessary,
use the
following
rated
fuses:
1(X)V
or
I20V ac
operation
-
MDL
3/8
(3/8A
slow
blow)
230V or
240V
ac
operation
-
MDL
3/16
(3/1
6A
slow
blow)
4-28. AC
Line
Voltage
Change
4-29. The
732A may
be
operated from
I(X)V,
120V,
220V, or
240V
ac ±
1
0%.
The
assigned
line
voltage
may be
changed
to
match
the
available
source using the
following
procedure.
Refer
to
Figure
4-5.
1.
Ensure
that
the
battery
is
charged
or an
appropriate
external
ac
or
dc
source is
connected
to
the
POWER
INPUT
jacks
on
the
rear
panel.
This
will
maintain
the
unit’s
stanardization
when ac
line
power is
removed.
The
BTRY
CHG
indicator on
the
front
panel
will
exlinquish
when
the battery is
fully
charged
and
the 7
32A is stll
connected
to the ac
power
source.
4-6