Resistance And Conductance Tests; Calibration Adjustments; Dc Calibration; Ac Calibration - Fluke 8050A Instruction Manual

MAINTENANCE
LINEAR VOLTAGE TEST
Table
4-7.
Resistance and Conductance Tests
STEP
SELECT DISPLAY
RANGE
INPUT
READING
1 200n
Short 00.00 to 00.04
2 200n lOOn 99.88 to 100.14
3 2kn 1 kn .9988 to 1.0012
4 20kn
10 kn 9.993 to 10.007
5 200 kn
100 kn 99.93 to 100.07
6
2000 kn 1 Mn 997.2 to 1002.8
7
20Mn 10Mn 9.972 to 10.028
8 2mS 1 kn .9985 to 1.0015
9 200 nS 10 Mn 99.30 to 100.70
4-42. CALIBRATION ADJUSTMENTS
4-43. Under normal operating conditions the 8050A
requires calibration once every year. Calibration
adjustments are also required after the instrument has
been repaired or if it fails any of the Performance Tests.
Test equipment required for the adjustments is listed in
Table 4-1. Figure 4-2 shows the location of all
adjustments for the following procedures. For
verification, do the Performance Tests after completing
the Calibration Adjustments. If portions of the
Calibration Adjustments cannot be completed, refer to
the Jumper Selection procedures given later in this
section.
NOTE
On the 8050A, set the POWER switch to ON
and allow the instrument to stabilize for
approximately 5 minutes. Perform the
calibration adjustments at an ambient
temperature of 23 ±5° C (79 ±~ F).
WARNING
CALIBRATION ADJUSTMENTS ARE
PERFORMED ON ENERGIZED CIRCUITS.
EXERCISE CAUTION AT ALL TIMES, AND
USE A NON-CONDUCTIVE TOOL FOR ALL
ADJUSTMENTS.
4-44. DC Calibration
4-45. Use the following procedure to perform a DC
Calibration:
I. Connect the DMM Calibrator to the 8050A as
follows: HI to the VjkOjS input connector and
LO to the COMMON input connector.
2. Select the DC V function on the 8050A.
3. Turn on the DMM Calibrator.
4-8
4. For each step in Table 4-8, select the range
shown, and adjust the DMM Calibrator for the
required 8050A voltage input level, then adjust
the indicated component to the display limits.
5. This concludes the DC Calibration
Adjustment. Remove power from the DMM
Calibrator before dismantling the test setup.
4-46. AC Calibration
4-47. Use the following procedure to perform an AC
Calibration:
l. Connect the DMM Calibrator to the 8050A as
follows: HI to the V/ kOj S input connector and
LO to the COMMON input connector.
2. Select the AC V function.
3. For each step in Table 4-9, select the range
shown, and adjust the DMM Calibrator to the
required 8050A voltage input level and
frequency, then adjust the indicated
component to the display limits.
4. This completes the AC Calibration procedure.
Remove power from the DMM Calibrator
before dismantling the test setup.
4-48. Jumper Selection
4-49. If the calibration adjustments do not bring the
instrument within specifications or if certain critical
components (VRI or U32) have been replaced, complete
one of the followingjumper selection procedures. Jumper
locations are shown in Figure 4-2.
4-50. US JUMPER SELECTION
4-51. The U5 jumper selection procedure should be
performed if VRI has been replaced or if Rll does not
have a sufficient adjustment range. Use the following
procedure to select the proper resistance for U5:
1.
Using the 5-pin connector (pin 537514)
provided with the replacement parts kit, short
MP20 jumper positions A-B-C-D.
2. On the 8050A, set the POWER switch to ON.
3. Adjust RII fully counterclockwise.
4. Select DC V function, 2V range.
5. Connect the DMM Calibrator to the 8050A as
follows: HI to the V/kOjS input connector and
LO to the COMMON input connector.
6. Adjust the DMM Calibrator to +l.8888V de.