Test Products International 440 - Manual (Page 21)

22 20
f. Measuring Diodes
CAUTION!
Do not attempt to make diode measurements with circuit
energized. The only way to accurately test a diode is to
remove it completely from the circuit before attempting to
measure it.
Instrument set-up:
FUNCTION BLACK RED MINIMUM MAXIMUM
TEST LEAD TEST LEAD READING READING
COM V
Ω
0.001V 2.000V
Measurement Procedure:
1. Disconnect power to circuit to be measured.
2. Plug black test lead into the COM input jack.
3. Plug red test lead into V
Ω
input jack.
4. Set the rotary switch to the function.
5. Connect black test lead to the banded end of the diode
and the red test lead to the non-banded end of the diode.
6. Reading on display should be between 0.5 and 0.8 volts.
7. Reverse test lead connections in 5 above.
8. Reading on the display should be OUCH (Overload).
NOTE: If diode reads 0 in both directions, diode is shorted.
If diode reads OUCH in both directions, diode is open.
Optional DMM Functions (refer to page 27)
POLA.
CHECK
F1 F2 F3 F4 F5