Measurement Operation(5)
D.Testing Diodes
(see figure 6)
red black
( figure 6)
Warning
To avoid damages to the Meter or to the devices under
test, disconnect circuit power and discharge all the
high-voltage capacitors before testing diodes.
Use the diode test to check diodes, transistors, and other
semiconductor devices. The diode test sends a current
through the semicondutor junction, then measure the
voltage drop across the junction. A good silicon junction
drops between 0.5V and 0.8V.
To test the diode out of a circuit, connect the Meter as
follows:
1. Insert the red test lead into the
V
Ω
terminal and
the black test lead into the
COM
terminal.
2. Set the rotary switch to
Ω
and press
SELECT
button to select measurement mode.
3. For forward voltage drop readings on any semiconductor
component, place the red test lead on the component’s
anode and place the black test lead on the component’s
cathode.
Model UT201/202: OPERATING MANUAL
19
