Fluke 87 III - Manual (Page 41)

Maintenance
33
Uses for the Zoom Mode (Models 83 and 85)
The relative mode, combined with the increased
sensitivity of the bar graph’s zoom mode, helps you make
fast and accurate zero and peak adjustments.
For zero adjustments, set the meter to the desired
function, short the test leads together, press
C ;
then connect the leads to the circuit under test. Adjust the
circuit’s variable component until the display reads zero.
Only the center segment on the Zoom bar graph is lit.
For peak adjustments, set the meter to the desired
function, connect the leads to the circuit under test; then
press
C . The display reads zero. As you adjust for
a positive or negative peak, the bar graph length
increases to the right or left of zero. If an overange
symbol lights
(
Û ®
), press
C
twice to set a new
reference; then continue with your adjustment.
Maintenance
Repairs or servicing not covered in this manual should be
performed only by qualified personnel as described in the
80 Series III Service Manual.
General Maintenance
Periodically wipe the case with a damp cloth and mild
detergent. Do not use abrasives or solvents.
Dirt or moisture in the terminals can affect readings and
can falsely activate the Input Alert feature. Clean the
terminals as follows:
1. Turn the meter off and remove all test leads.
2. Shake out any dirt that may be in the terminals.
3. Soak a new swab with a cleaning and oiling agent
(such as WD-40). Work the swab around in each
terminal. The oiling agent insulates the terminals
from moisture-related activation of the Input Alert
feature.