Rotary Switch; Performance Tests; A Basic Operability Test - Fluke 87 III Series Service Information

80 Series III
Service Information
3. Moisten a new swab with a cleaning and oiling agent (such as WD40). Work this

Rotary Switch

To clean the rotary switch potentiometer, do the following:
1. Remove the circuit board assembly as described earlier under "Removing and
2. From the back of the circuit board assembly, push the switch shaft in, and remove
3. Clean the ptf contact assembly and the potentiometer on the circuit assembly with
4. Using a Q-tip, apply a thin film of W. F. Nye Gel Lubricant, #813S (Fluke PN
5. Push and secure the ptf contact assembly back on to the switch shaft.
6. Reassemble the circuit assembly, the shields, and case halves as described earlier
7. Perform the procedures under "Performance Tests".

Performance Tests

The following performance tests verify the complete operability of the Meter and check
the accuracy of each Meter function against the Meter's specifications.
Accuracy specifications are valid for a period of one year after calibration, when
measured at an operating temperature of 18°C to 28°C and at a maximum of 90 %
relative humidity.
To perform the following tests, it is not necessary to open the case; no adjustments are
necessary. Merely make the required connections, apply the designated inputs, and
determine if the reading on the Meter display falls within the acceptable range indicated.
If the Meter fails any of these tests, it needs calibration adjustment or repair.

A Basic Operability Test

To check the basic operability of an 80 Series III Multimeter, do the following:
1. Turn the rotary switch to
The display should read 1.000 kΩ ± 5 digits.
2. With the rotary switch still at
14
swab around in each of the four terminals.
The oiling agent insulates the terminals from moisture-related shorting and ensures
against false Input Alerts.
Reinserting the Circuit Board Assembly".
the polymer thick film (ptf) contact assembly.
alcohol. Blow these parts dry with clean, dry air.
926084), to the entire surface of the ptf pattern and the hole in the center of the
pattern. It is important that the grease be applied in a film of consistent thickness
such that grease does not accumulate on the ptf wiper contacts. Remove excess
grease with a dry Q-tip. No portion of the ptf pattern should be left unlubricated.
under "Reassembling the Meter Case".
inputs. (If you are using a test probe, touch the half of the input contact nearest the
LCD.)
end of the test lead into the
The beeper emits an Input Alert tone if the fuse is good.
and connect a test lead from the Vto the
Ω
Ω,
test the A input fuse (11 A) by inserting the plug
A input.
mA µA