Making Measurements 2
Testing Diodes
U1271A/U1272A User’s Guide 81
Your multimeter can display diode forward bias of up to
approximately 3.1 V. The forward bias of a typical diode
is within the range of 0.3 V to 0.8 V; however, the reading
can vary depending on the resistance of other pathways
between the probe tips.
3 Reverse the probes (as shown in Figure 2- 22) and
measure the voltage across the diode again. Assess the
diode according to the following guidelines:
• A diode is considered good if the multimeter displays
in reverse bias mode.
• A diode is considered shorted if the multimeter
displays approximately 0 V in both forward and reverse
bias modes, and the multimeter beeps continuously.
• A diode is considered open if the multimeter displays
in both forward and reverse bias modes.
Figure 2-20 Open diode display
If the beeper is enabled during diode test, the multimeter
will beep briefly for a normal junction and sound
continuously for a shorted junction, below 0.050 V. See
“Changing the beep frequency” on page 130 to disable the
beeper.
To Next Page
Loading...
