Fluke 8050A Instruction Manual page 60

MAINTENANCE
CALIBRATION ADJUSTMENTS
Table
4-8.
DC
Calibration
RANGE
DISPLAY
LIMITS
1
2V
+1.
9000V
R11
+1.9000
exactly
2
200
mV
+190.00
mV
R12
+1 90.00 exactly
3
200
V
+190.00V
R5
+1 90.00 exactly
4
1000V
dc + 1000.0V
R6
+1000.0
exactly
R11
can not be adjusted
to the
DISPLAY
LIMIT,
refer to the
U5
jumper
selection
procedures
in
Section 4
of this
manual.
Table
4-9.
AC
Calibration
STEP RANGE
8050A
VOLTAGE
INPUT
ADJUST
DISPLAY
LIMITS
LEVEL
FREQ
2
3
4
5
2V
2V
R7
ar
2V
20V
200V
Cl
ar
*Use
a
1
,9000V
100.0
mV
d
R29
are interacting
Short
circuit
19.000V
100.00V
d
C2
are interacting
a
n insulated screwdrive
200 Hz
200 Hz
adjustments.
Re
lOkHz
10
kHz
djustments.
Repe
r
for these adjust
R7
R29
aeat until
both
are
w
cr
C2*
at until
both
are wit
Tients.
I
.
1.8995
to 1.9005
[T>
,0999
to .1001
[|>-
thin
their
limits.
Less
than
40
digits
18.990
to
19.010
99.95
to
100.05
hin
their limits.
If
R7
cannot be adjusted to the
DISPLAY
LIMITS,
refer
to the
U33 jumper
seiecter
procedure
in
Section 4
of
this
manual.
If
the display
is
not within
limits in step
3 or
R29
is
outside
adjustment range procedure
range, refer to the
RMS
Converter Offset Adjustment procedure
in
Section 4 of
this
manual.
7.
Turn on
the
DMM
Calibrator.
8.
Compare
the
8050A
display to the
LOW
and
HIGH
display readings
in
Table 4-10
and
find
the
DISPLAY
READING
that the
8050A
display
is
between. Cut
out the portion of
the
jumper
as
shown under
the
JUMPER
CONFIGURATION
heading
that corresponds
to the
DISPLAY READING.
9.
Perform
the Calibration Adjustments.
4-52.
U33
JUMPER
SELECTION
4-53.
The U33 jumper
selection
procedure should be
performed
if
the
RMS
Converter(U32) has been
replaced
or
if
R7
does not have a
sufficient
adjustment
range.
Use
the following procedure
to select the
proper
resistance for
U33:
1.
Using
the 4-pin connecter (p/n 537522)
provided with
the
replacement
parts
kit,
short
MP2I
jumper
positions
E-F-G.
2.
On
the
8050A,
set the
POWER
switch to
ON.
3.
Adjust
R7
fully
clockwise
and
adjust
R29
the
center of
its
range.
4.
Select the
AC
V
function,
2V
range.
5.
Connect
the
DMM
Calibrator
to the
8050A
as
follows:
HI totheV/kn/S
input connector and
LO
to
the
COMMON
input connector.
6.
Adjust
the
DMM
Calibrator for l.OOOOV ac
rms,
at
200Hz.
7.
Turn on
the
DMM
Calibrator.
8.
Compare
the
8050A
display to the
DISPLAY
READING
columns
in
Table
4-11
and
find
which
LOW
and
HIGH
values that the
8050A
display reading
is
between. Cut
out
the
portion
of the
jumper
as
shown
under
the
JUMPER
CONFIGURATION
heading
that corresponds
to the
DISPLAY READING.
4-10