Digital Multimeter With Voice Readout
2218202
voltage appears.
4. If you want the meter to announce the test result, press the switch on the red test lead
for less than 1.5 seconds. If you want the meter to be alluminated press the switch on the red
test lead for more than 1.5 seconds, and the meter will be lit for 30 seconds.
Measuring AC Voltage Riding on a DC Source Bias
To measure an AC voltage superimposed on a DC voltage source bias, you must first measure the
DC and AC voltages separately, then compute the peak voltage using this formula:
AC voltage
Peak voltage
= DC v.707
Warning
: To avoid injury to yourself or damage to your meter, never try to measure an AC voltage
that is riding on a DC source bias where the peak voltage exceeds 500 V with respect to earth
ground.
Caution
: Never try to measure any voltage more than 30V AC on a DC source bias.
Follow these steps to measure AC voltage:
1. Set the selector to DC V.
2. Connect the test leads to the circuit you want to test. The display shows the DC voltage.
3. Disconnect the test leads from the circuit.
4. Set the selector to AC V.
5. Connect the meter’s test leads again to the same circuit you tested in Step 2. The display
shows the AC voltage.
6. To compute the peak voltage, refer to the formula seen above.
Measuring resistance
The resistance measuring circuit in your meter compares the voltage gained through a known
internal resistance with the voltage developed across an unknown resistance.
Warning
: Be sure the circuit under testing has all power removed and any associated capacitors
are fully discharged before you make a resistance measurement.
1. Set the selector to OHM/DIODE/CONTINUE.
Caution
: Your meter has a circuit to protect the resistance range from over-voltage. However, to
prevent accidentally exceeding the protection circuit’s rating and to ensure a correct
measurement, never connect the test leads to a source of voltage while the selector is set to
OHM/DIODE/CONTINUE.
Note
:
1. If there is no resistance connected across the test leads or the measured value exceeds the
range you set, OL appears when you set the selector to OHM. This is normal.
2. Connect the test leads across the circuit you want to measure. Or, remove one of the
component’s leads you want to measure from its circuit and connect the test leads across the
component. The meter displays the reading in the chosen range.
3. If you want the meter to announce the test result, press the switch on the red test lead
for less than 1.5 seconds. If you want the meter to be alluminated, press the switch on the red
test lead for more than 1.5 seconds, and the meter will be lit for 30 seconds.
Checking diodes
This measurement lets you check diodes, transistors, and other semiconductors for opens, shorts,
and normal operation. It also lets you determine the forward voltage for diodes. (This is handy
when you need to match a diode).
Caution
: Do not connect the test leads to a source of voltage when you set the selector to Diode.
This could damage the meter or circuit being tested.
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