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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
0.001V 2.0000V
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
input jack.
4. Set the rotary switch to the
function.
5. Connect the 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 the display should be between 0.5 and 0.8
volts.
7. Reading test lead connections in 5 above.
8. Reading on the display should be OFL(Overflow).
NOTE: If diode reads 0 in both directions, diode is
shorted. If diode reads OFL in both directions, diode
is open.
e. Measuring Resistance
WARNING!
Do not attempt to make resistance measurements with
circuit energized. For best results, remove the resistor
completely from the circuit before attempting to measure
it.
NOTE:
To make accurate low ohm measurements, short the ends
of test leads together and record the resistance reading.
Deduct this value from actual readings.
Instrument set-up:
FUNCTION BLACK
RED
MINIMUM
MAXIMUM
TEST LEAD
TEST LEAD
READING
READING
COM
0.01
Ω
50.000M
Ω
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
input jack.
4. Set the rotary switch on the DMM to the
function.
5.Connect the test leads to the circuit to be measured.
6. Read the resistance value on the LCD.
