Velleman DVM9912 - Manual (Page 8)

DVM9912 VELLEMAN 8
DIODE CHECK
1. Set the function switch to the position.
2. The symbol will appear on the screen.
3. Insert the black test lead banana plug into the negative (-) jack (COM) and the red test lead banana plug
into the positive (+) jack (Ω).
4. Touch the test probe tips to the diode or semiconductor junction you wish to test. Write down the meter
reading.
5. Reverse the probe polarity by switching probe position. Write down this reading.
6. The diode or junction can be evaluated as follows:
A. If one reading shows a value and the other reading shows OL, the diode is good.
B. If both readings show OL, the device is open.
C. If both readings are very low or 0, the device is shorted.
NOTE: The value indicated on the display during the diode check is the forward voltage.
FREQUENCY MEASUREMENT
1. Set the function switch to the Hz% position.
2. Insert the black test lead banana plug into the negative (-) jack (COM) and the red test lead banana plug
into the positive (+) jack (F).
3. Touch the test probe tips to the circuit under test.
4. Read the frequency on the display. The digital reading will indicate the proper decimal point, symbols (Hz,
kHz) and value.
CAPACITANCE MEASUREMENTS
1. Set the function switch to the CAP position (“nF” and a low value will appear in the display).
2. Insert the black test lead banana plug into the negative (-) jack (COM) and the red test lead banana plug
into the positive (+) jack (CAP).
Touch the test leads to the capacitor to be tested. The display will indicate the proper decimal point, value
and symbol.
TEMPERATURE MEASUREMENTS
1. If you wish to measure temperature in o F, set the function switch to the o F range. If you wish to measure
temperature in o C, set the function switch to the o C range.
2. Insert the type K thermocouple probe black test lead banana plug into the negative COM jack and the red
test lead banana plug into the positive TEMP jack.
3. Touch the temperature probe head to the part of which you wish to measure the temperature. Keep
touching the part under test until the reading stabilises (about 30 seconds).
Read the temperature on the display. The digital reading will indicate the proper decimal point and value.
WARNING: To avoid electric shock, do not test any diode that has voltage on it.
WARNING: To avoid electric shock, disconnect power to the unit under test and discharge all
capacitors before taking any capacitance measurements. Remove the batteries and unplug
the line cords.
WARNING: To avoid electric shock, disconnect both test probes from any source of voltage before
carrying out a temperature measurement.