AM300 V1.1 6/07
6
Resistance Measurements
WARNING:
To avoid damage to the meter,
do not apply voltage to the meter when
measuring resistance. Ensure that the circuit, device, or component under test is
disconnected from power before measuring resistance.
1.
Insert the black test lead into the negative COM terminal and the
red test lead into the OHMS positive terminal.
2.
Set the display scale to the OHMS position using the thumbwheel
switch.
3.
Ensure that the Pointer Lock switch is set to the right-most
position so that the pointer may freely move.
4.
With the test leads open, adjust the meter zero so that the pointer
is over the
∞
symbol.
5.
Touch the test lead tips together and adjust the 0 Ohms adjust
until the pointer is over the 0 ohms position.
6.
Touch the test probe tips across the circuit or component under
test.
7.
The analog display pointer will indicate the resistance reading.
Pointer Lock Function
The Pointer Lock switch freezes the pointer’s position and can be used as a ‘data hold’
feature. This feature is useful in dimly lit or hard to reach locations.
Maintenance
WARNING:
To avoid electrical shock, disconnect the meter from any circuit and remove the test leads from
the input terminals before opening the case. Do not operate the meter with an open case.
Cleaning and Storage
Periodically wipe the case with a damp cloth and mild detergent; do not use abrasives or
solvents. If the meter is not to be used for 60 days or more, remove the battery and store it
separately.
Battery and Fuse Replacement
1.
Remove the two (2) Phillips head screws at the rear of the meter.
2.
Carefully open the meter housing.
3.
Replace the 1.5V ‘AA’ battery if necessary
4.
Replace the fuse if necessary with a 0.5A / 250V glass fuse (6mm x 30mm) or
equivalent. Note that a spare fuse is provided inside the meter housing.
5.
Close the meter and replace the meter screws securely.
W
