Testing The Display; Testing The Rotary Switch - Fluke 80 SERIES III Service Information

3. Then test the mA µA input fuse (0.440 A) by inserting the plug end of the test lead
mA µA
into the
The beeper emits an Input Alert tone if the fuse is good.
If the Meter fails to operate properly:
•
Check the battery and fuses and replace as needed.
•
Verify that you are operating the Meter correctly by reviewing the operating
instructions found in the Users Manual.
To complete a comprehensive performance test and verify the accuracy of each Meter
function and operation, perform the remainder of the tests under "Performance Tests".

Testing the Display

Turn the Meter on and press any push-button to hold the Meter in Display Test mode.
Compare the display with the appropriate example in Figure 4.
83
III MULTIMETER
85
III
TRUE RMS MULTIMETER

Testing the Rotary Switch

This test verifies the operation of the rotary switch function selector.
The function selector circuit relies on the interface between a ptf region on the circuit
assembly and a rotating contact assembly on the switch shaft. The rotary switch test
exercises this interface by checking the various range codes and displaying their
representative numbers.
To perform the rotary switch test, do the following:
1. Hold down Kwhile turning the rotary switch from
2. Release K.
Normal Meter functions are now disabled, and a number appears in the display.
3. Compare the number on the display with the number for the V dc (L) function in
Table 3.
The display should read -32 (±12).
4. Repeat this test for each position on the rotary switch.
5. To exit the rotary switch test mode, turn the rotary switch to
function selection.
input.
Figure 4. Display Test
87 TRUE RMS MULTIMETER
III
to L.
OFF
OFF
Multimeters
Performance Tests
ek9f.eps
, then back to any
15