Required Test Equipment; Display Pcb Access - Fluke 8050A Instruction Manual

MAINTENANCE
ACCESS PAOCEDURES
Table 4-1. Required Test Equipment
INSTRUMENT TYPE
REQUIRED CHARACTERISTICS
RECOMMENDED MODEL
DMM Calibrator
DC Voltage 0 to 1OO0V ±.006% John Fluke Model 5100B
AC Voltage
100 Hz 0 to 750V ±.06%
200 Hz 0 to 2V ±.O6%
1 kHz 0 to 750V ±.06%
10 kHz 0 to lOOV ±.O6%
20 kHz 0 to lOOV ±.1%
50 kHz 0 to 20V ±.5%
DC Current 0 to 2000 rnA ±.035%
AC Current 19 rnA. 100 Hz ±.1%
Resistance
loon,l kn ±'Ol%
10 kn, 100 kn ±.OO5%
1 Mn, 10 Mn ±.05%
Digital Multi-Meter (DMM)
.1 mV resolution
John Fluke Model 8020B
Calibration Leads 24" Shielded cable with a double
Pomona 2BC-24
banana plug at both ends
4-11. CALIBRATION ACCESS
4-12. Use the following procedure to gain access to the
calibration adjustments or the backup fuse (F2):
1.
Set the POWER switch to OFF.
2. Remove the power cord from the rear of the
instrument.
3. Remove the screw located directly below the
power receptacle.
4. Grasp the front panel and slide the instrument
out of the case.
5. The backup fuse and calibration adjustments
are now accessible on the underside of the
instrument (as viewed from the front panel).
NOTE
With the power cord replaced. the instrument
is operational for troubleshooting.
WARNING
DANGEROUS VOLTAGES EXIST ON THE
PCB ASSEMBLIES WHEN ENERGIZED.
EXERCISE EXTREME CARE WHEN
WORKING ON AN ENERGIZED CIRCUIT.
6. To reassemble, reverse the previous procedures
in a logical order.
4-13. DISPLAY PCB ACCESS
4-14.
Use the following procedure to access the Display
PCB for troubleshooting:
I. Complete the Calibration Access procedure.
2. Refer to Figure 4-1. Turn the instrument over
and remove the indicated screws.
3. The LCD, POWER switch, and RELATIVE
switch are mounted on the Display PCB
Assembly. Gently push on the LCD and
POWER switch, sliding the assembly towards
the rear of the instrument until the LCD and
the switches clear the front panel and the right-
hand side pcb edge slot.
4. Flip the Display PCB over on the right side of
the instrument.
CAUTION
The Display PCB Is connected to the main pcb
by
a
flexible ribbon cable (Interconnect). This
cable remains attacheCi for service operation.
Avoid straining the Interconnect cable while
working on the Instrument.