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Model UT804: OPERATING MANUAL
Figure 3-12. Diode Test
G. Testing Diodes
Warning
To avoid harms to you, please do not attempt to
input voltages higher than 60V DC or 30V AC.
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, set up the Meter as
Figure 3-12 and proceed as follows:
1. Insert the red test lead into the
terminal and the
black test lead into the
COM
terminal.
2. Set the rotary switch to
; and press button to
select
measurement mode.
3. For forward voltage drop readings on any
semiconductor component, place the red test lead
