Multimeter  (220-0179)         Diode Check            Faxback Doc. # 6269

The meter can check most diodes, for open, shorted, or normal conditions.

Caution:  Do not connect the test leads to a source of voltage when you
set the function switch to diode CHECK.

Before checking a DIODE be sure to remove power from the circuit under
test.

Follow these steps to check a diode.

1.  Set the function switch to DIODE CHECK.  The DIODE symbol and OL
    appear on the display.

2.  Connect the probes to the semiconductor device to be tested - red
    lead to anode and black lead to cathode - and note the display
    reading.

3.  Reverse the probes, and note the second reading.  The type and
    condition of the tested semiconductor device is:

1st reading      2nd reading       Semiconductor type      Condition

0.2-0.3             OL             germanium               good
0.5-0.6             OL             silicon                 good
OL                  OL             germanium/silicon       open
very small          very small     germanium/silicon       shorted

Notes:

The values displayed during the diode check show the actual forward
voltage (max. 2.0V).  If the voltage exceeds 2.0V, OL is displayed
and the diode check cannot be made.

You can also check LEDs (light emitting diodes) using the same procedure.

(RLR/smc-05/16/94)