Triplett 630 - Page 9

е Whenever possible, the test probes should be disconnected from
the voltage source (or the source shut off) before the range switch
position is changed. This practice will result in an increased life and
reliability for the VOM.
• The Meter Zero Adjust Screw is located on the lower center of the
meter cover. It should be periodically adjusted so the meter pointer
is on zero with no input into the VOM.
• Readings on the sensitive voltage, current and resistance ranges
may sometimes be different than calculated values. Thermo-electric
or electro-chemical reactions can sometimes generate voltage (or
current) in a circuit due to elevated temperatures from soldering,
contact of dissimilar metals, chemical fumes or moisture. Also, the
fingers should never touch the metal parts of the test probes since
body resistance can cause erroneous readings—particularly on the
high ohmmeter ranges.
ө CAUTION: Always observe the following rules and procedures
when making measurements in high voltage circuits.
1. Turn off equipment or other source of voltage, before con-
necting test probes. Make sure no capacitors in the circuit
being tested remain charged to a high voltage.
2. Install alligator clips on test probes. While holding the in-
sulated section of the test probe, check circuit to see if any
voltage (or current) is present. If no voltage is present, con-
nect the alligator clips to the circuit to be measured.
3. Turn on equipment, or voltage source, and take required
readings. DO NOT handle or touch the VOM, test leads or
test probes with power source turned on.
Observing the above rules and precautions will result in con-
tinued accurate measurements with your VOM at increased safety
to equipment and personnel.