Performance Tests; Display Test - Fluke 8050A Instruction Manual

MAINTENAMCE
4-27.
Clean
the front panel
and
case
with
a mild solution
of detergent
and
water.
Apply
the solution
with
a soft
cloth.
Do
not apply
the solution directly to the front
panel.
Clean
dust
and
debris
from
the pcb's with low-
pressure (20
psi)
dry
air.
Clean contaminates from
the
pcb's with isopropyl alcohol
and
a
soft
brush. Rinse with
demineralized water while scrubbing
with a
soft
brush.
To
dry
the pcb's,
remove any
ICs
in
sockets
and
use low-
pressure dry
air,
then
bake
at
50
to
60°C
(124
to 140°F)
for
24
hours.
Replace any components removed
for
cleaning
and reassemble
the instrument.
4-28.
PERFORMANCE
TESTS
4-29.
The
performance
tests
are
used
to
compare
the
8050A
performance
with the
list
of
specifications given
in
Section
1.
We
recommended
that
you
run
the
performance
tests
for
incoming
inspection
and
periodic
calibration. If the
instrument
fails
any
of
the
performance
tests,
then
calibration
adjustment
and/or
repair
is
needed.
4-30.
initial
Procedures
4-31.
Before begining each of the
tests,
perform
the
following:
1.
Remove
ail test
leads.
2.
Check
the fuses and,
if
necessary, replace.
3.
Set the
POWER
switch
to
ON,
and
allow the
8050A
to
stabilize
for
approximately
5
minutes.
Conduct
the
tests in
an environment
with
an
ambient temperature of
23
±
5°C
(73
±
9°F)
and a
relative
humidity of
less
than 80%.
4-32.
Display Test
4-33.
Use
the following
procedure
to verify the proper
operation of the
LCD:
1.
Select
the kfl function, 200fl range.
2.
Verify that the overrange indicator
(I)
is
displayed.
3.
Connect
the red
test
lead to the
V/kO/S
input
connector
and
the black
test
lead to the
COMMON
input connector.
4.
Refer
to
Table
4-3.
Short
the
test
leads together
and
verify that the display reads
as
shown
for
each of the resistance ranges.
Table
4-3. Display Test
SELECT
RANGE
DISPLAY
200Q 00.00*
2
kO
.0000*
20
k£2
0.000
200
kfl
00.00
2000
kn
000.0
20 Mfl
0.000
*Due
to test lead
.resistance,
the
least significant
digit(s)
may
fluctuate
by
several counts.
5.
Select the
DC
V
function, press the
REF
Z
switch
to the
in
position (on)
and
verify that
four decimal
points
appear on
the display.
6.
Select the
200V
dc
range.
7.
Connect
the
DMM
Calibrator
to the
8050A
as
follows:
HI
to the
V/ kO/
S
input
connector and
LO
to the
COMMON
input connector.
8.
Adjust
the
DMM
Calibrator
until the
8050A
displays
+
188.88V dc
exactly.
9.
Verify that
all
segments of the
8050A
LCD
are
illuminated
and
the
HV
annunciator appears
in
the display.
1
0.
Set the
DMM
Calibrator for
a -59V dc
output.
1
1
.
Verify that the
H
V
annunciator disappears and
the polarity indicator changes to - (negative).
12.
Select the
dB
function
on
the
8050A, then
set
the
RELATIVE
switch to
ON
(in).
13.
Verify that the
dB
and
REL
annunciators
are
illuminated.
14.
This concludes
the
Display
Test.
Remove
power from
the
DMM
Calibrator before
dismantling
the
test
setup.